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vizion
19-Feb-2011, 12:44
I am wanting to do some macro using with my TK 45 S.

I am wondering if any macro workers would be willing to tender some advice on suitable lenses and comparative performance. My main interest with macro work is photographing insects.

Thanks in advance

David

Bob Salomon
19-Feb-2011, 12:51
What magnification do you need to do?

vizion
19-Feb-2011, 15:44
What magnification do you need to do?
Depends on the insect <chuckles>
My objective is to go from 1:1 at the lower end to recording a bug with a length of 1/10th of an inch (2.5mm) & rendering it into 75% (3.75 inch or approx 95mm) of the film width without distorting the image.

The question is what are good choices of lenses & techniques to cover the range. There are the normal limitations imposed - fast lenses preferable to slow (bugs move) lighting challenges - I have things like ring flash etc but artificial lighting produces problems with highlights and I prefer dull daylight - hence a preference for faster lenses.

Depth of field requirements produce problems making for hard choices (push the film to get shorter exposure times with greater depth of field).

Bob Salomon
19-Feb-2011, 16:18
Depends on the insect <chuckles>
My objective is to go from 1:1 at the lower end to recording a bug with a length of 1/10th of an inch (2.5mm) & rendering it into 75% (3.75 inch or approx 95mm) of the film width without distorting the image.

The question is what are good choices of lenses & techniques to cover the range. There are the normal limitations imposed - fast lenses preferable to slow (bugs move) lighting challenges - I have things like ring flash etc but artificial lighting produces problems with highlights and I prefer dull daylight - hence a preference for faster lenses.

Depth of field requirements produce problems making for hard choices (push the film to get shorter exposure times with greater depth of field).

You have a couple of problems. First you have to work within the 20" of bellows on the TK + how ever much you can add with an extension board. But you mention distortion. Modern lenses don't distort but shorter lenses will foreshorten the image so those things closer to the lens will appear larger then those things further away. Is that what you call distortion?

A macro lens like the 120 mm Apo Macro Sironar will normally work for most of what you want but would have more foreshortening then a longer macro like the 180 mm. But the bellows length will not let you get the ratios you want.
These are 5.6 lenses but at your ratios no lens will be very fast thanks to bellows extension and you want depth of field o the speed of the lens s not going to make much difference other then for focusing.

pdmoylan
19-Feb-2011, 16:26
Refrigerating the subjects prior to shooting might help the movement problem. Some don't approve of this method.

vizion
20-Feb-2011, 03:40
You have a couple of problems. First you have to work within the 20" of bellows on the TK + how ever much you can add with an extension board.

I should have mentioned I was also struck by this problem and have, in anticipation, designed an extension system which will add up to 7" (175mm) for macro work. I will be doing the engineering in March and will report back when I have some results.

Currently I have is a Schneider- Kreuznach Componon-S 5.6/180 mounted on a Synchro-Compur shutter.


But you mention distortion. Modern lenses don't distort but shorter lenses will foreshorten the image so those things closer to the lens will appear larger then those things further away. Is that what you call distortion?

A small amount of DOF distortion cannot be avoided but I would like to restrict it to the barest minimum.


A macro lens like the 120 mm Apo Macro Sironar will normally work for most of what you want but would have more foreshortening then a longer macro like the 180 mm.
Bearing in mind my Componon-S 5.6/180 mounted on a Synchro-Compur shutter plus the possibilities opened up by a 7" (175mm) extension system additional thoughts would be much appreciated.
Thanks in advance
David

vizion
20-Feb-2011, 03:48
Refrigerating the subjects prior to shooting might help the movement problem. Some don't approve of this method.

Unfortunately that includes me mainly on practical grounds because it eliminates the chance of shooting images showing the reactions between multiple insects and between the insect and its activities in the environment. The freezing techniques is really only useful for shooting specimen records for species identification purposes.

pdmoylan
20-Feb-2011, 04:55
Not to question your methodology, but Mark Moffet (National Geo) who has become quite famous for his incredible photography of ant behavior incorporates Olympus macro lens (38mm) as well as Canon macro lens on 35mm film (and now presumably digital), of course with multiple flash units, while years ago Stephen Dalton (scientist) became world renowned for his images of flying insects with elaborate infrared tripping devices. He started using Leica macro lens and bellows, added Hasselblad and Nikon 105micro later, all with many powerful flash units, both for subject and backgrounds.

As a photographer of such subjects, without reflex viewing and portability, I would find a Technikardan essentially unusable for this adaptation unless one was able to attract insects to the exact focus spot (pheromones?). You didn't mention whether you were a biologist (by profession or design).

I am not familiar with the magnification rates of MFD lenses. Assuming you could attain the right magnification, it would seem to me the best way to go to obtain enough resolution to print out massive sized images. A Nikon D3x or comparable Canon FF 21mp+ camera with macro lenses would be immensely easier and still give you quality large sized prints.

vizion
20-Feb-2011, 06:42
As a photographer of such subjects, without reflex viewing and portability, I would find a Technikardan essentially unusable for this adaptation unless one was able to attract insects to the exact focus spot (pheromones?). You didn't mention whether you were a biologist (by profession or design).

I am something of an experimenter as well as a beekeeper! This means I know how to get my subjects and their parasites (around 1.5 -2.5mm) exactly where I want them to be and keep them there naturally. The same thing goes for my greenhouse & its insects! I also have what is currently a rather Heath Robinsonian rig for monitoring the TK and the GG screen remotely from a laptop with shutter operation directly from the keyboard. After some testing I will make more information available here and hopefully a less weird version will be possible<grins>! I also want to add shutter and focus controls using small stepping motors.

For me 5x4 is an ideal format giving great detail and a forerunner for experimenting with a 10x8 version of my rig.

I have done what you suggested with a digital slr (using canon 5d) and I am interested to see how far LF can push the boundaries and obtain much greater detail.

I would be interested to hear of more information about lens choices especially for higher magnification ranges.

david

pdmoylan
20-Feb-2011, 06:55
There are many posts regarding lenses for jewelry photography. Using the search engine you might find the answer you are looking for.

Dan Fromm
20-Feb-2011, 07:03
I'm with pdmoylan. A view camera isn't the right tool for photographing mobile subjects at relatively high magnification. Especially in "the field."

I took up photography with the goal of shooting unconstrained fish in aquaria. This is nearly your problem, David. In 1971 the best tool for that job was a 35 mm SLR with a macro lens. Hand held, focused by moving the camera/lens to track the subject. A major part of that art is arranging the tank so the fish does what the photographer wants to record where the recording is easy.

The techniques I developed for shooting fish transferred directly to shooting flowers and insects at low magnification -- the highest my usual rig allows is 0.88:1 and shooting that high handheld isn't easy, focus is too easy to lose -- in the field. Multiple flash units attached to the camera body or the lens' filter threads, calibrated so that I know which aperture to use given magnification and flash power settings. No thinking required, just consult the tables, set up, compose, focus, push the button.

The ancients used focusing frames with non-SLRs to work more rapidly closeup. Most often fixed focus cameras with a + diopter. For an explanation, see Gibson, H. Lou. Close-Up Photography and Photomacrography. 1970. Publication N-16. Eastman Kodak Co. Rochester, NY. 98+95+6 pp. The two sections were published separately as Kodak Publications N-12A and N-12B respectively. Republished in 1977 with changes and without the 6 page analytic supplement, which was published separately as Kodak Publication N-15. 1977 edition is ISBN 0-87985-206-2. Focusing frames are discussed in the Close-up section, -A.

I've tried to make a couple of focusing frames for shooting flowers with a handheld 2x3 Graphic and electronic flash, haven't yet come up with a design I'm willing to build and try to use. Haven't come up with a good set up procedure either, and am not sure I can see exactly where the plane of best focus will be.

So you'll know and perhaps reconsider, I have a set of good lenses made for shooting above 1:1 and the adapters needed to mount them on a Nikon, have tried working at 5:1 handheld. Luminars, Minolta Compact Bellows with strings of adapters, supplemental tubes as needed, ... Short answer, don't bother. Keeping focus is very difficult. Perhaps with digital where the incremental shot is free and with a sufficiently powerful repeating flash. But not with my gear.

pdmoylan's remark about separate flashes for the backgrounds is great. That's the only way to control the background's lighting; flash(es) mounted on camera and lens usually make a black background.

David, before you proceed further have your sanity checked. You want to shoot a 2.5 mm insect and get a 95 mm image. Fine, wonderful, but that's 38:1. 38:1 requires 39 * f extension. You haven't thought about what that means for the 120 mm lens that doesn't appeal to you. You're nuts or extremely clueless.

vizion
20-Feb-2011, 08:17
I'm with pdmoylan. A view camera isn't the right tool for photographing mobile subjects at relatively high magnification. Especially in "the field."

I took up photography with the goal of shooting unconstrained fish in aquaria. This is nearly your problem, David.

With respect I do not think you have carefully read what I have said. I have other ways of getting the subject to the exact location I need them to be so I do NOT need to move the camera. The subject will carry out the action I want to record in the exact spot where the camera is pointing. I have done this successfully with 5D remote controlled on tripod. So I know the set up works. the same thing goes for lighting etc.



David, before you proceed further have your sanity checked. You want to shoot a 2.5 mm insect and get a 95 mm image. Fine, wonderful, but that's 38:1. 38:1 requires 39 * f extension. You haven't thought about what that means for the 120 mm lens that doesn't appeal to you. You're nuts or extremely clueless.

The 2.5mm insect to which I referred is the parasite with a bee. I can see you read this as a desire for the parasite to be full frame whereas it would be shown with all or part of the bee. It looks to me as though I can (with my current extension design) reliably expect to work with at least 27inch of bellows plus 3" of tube extension giving the equivalent of 30" of bellows (say 750mm). Now a bee is a little over 15mm. So to show the bee 95mm wide would require 6.33:1. However I do want to do a lot better than that. A 50mm lens would give me 15:1 but at what point can I get a lens which would meet both my magnification requirements with minimal DOF distortion?

This may mean I need to increase my bellows extension well beyond 7" (this is my calculated stability limit using a single tripod) if so by how much? I reckon the extension system I have designed could be reliably scaled from 7" up to at least 25" (giving equivalent of 48" of bellows using a double tripod arrangement) after which there are some engineering design issues which would need very careful restructuring.

I would like to feel people were concentrating on my questions about lens choices and leave me to solve the inevitable problems I would face on using them. My original posting put my question much more simply:


I am wanting to do some macro using with my TK 45 S.

I am wondering if any macro workers would be willing to tender some advice on suitable lenses and comparative performance. My main interest with macro work is photographing insects.

David

I know people want to help and what I am looking for is advice on macro lenses and their comparative performance on a 4x5. I am sorry if I have succeeded in confusing people by answering questions in a way that took focus away from my original very simple question.

Thanks

David

Dan Fromm
20-Feb-2011, 09:55
David, you really need to read a good book on the subject. You think you know what you need to know and are trying to ask about that and nothing else. Your relatively short questions reveal, however, that in spite of your success with a Canon you need to know more than you think you do. Two book suggestions. Lester Lefkowitz' The Manual of Closeup Photography, Brian Bracegirdle's Scientific Photomacrography. Bracegirdle is drier than Lefkowitz, both cover the same subjects.

Your focus on lenses is silly. There's no rational basis for choice among the better grade of dedicated macro lenses. They are all much better than good enough, differences among them are trivial. You can't make a bad mistake with any of them as long as the one you get is in good condition.

I'm not referring to the excellent lenses that Mr. Salomon suggested but to lenses made specifically for working above 1:1. The good ones are made by microscope manufacturers, e.g., Zeiss (Luminars), Leitz (Photars), Nikon (Macro Nikkors). Canon and Olympus also make good lenses in this class. Find out which focal length of any of the good brands (a) will cover 4x5 at your desired range of magnifications and (b) whose best range of magnifications includes your desired range. Then buy one and go. Remember that all of these lenses have optimal ranges of magnifications. None is best for all magnifications.

At the magnifications you want to work at (still not stated clearly) there's one sleeper, the 55/2.8 MicroNikkor AI/AIS. Reversed and shot at f/4 it is competitive with the 63 Luminar at f/4.5. Posters on the French LF forum insist that the 55/3.5 MicroNikkor is even better but I don't know whether they've done the comparison or simply found the f/3.5 good. I have both, have never tested the f/3.5. The f/2.8 is good enough.

The 55 MicroNikkors aren't significantly better (or worse) than comparable lenses from other makers so I suspect their competitors would be equally usable reversed above 1:1. Subject, for all including the MicroNikkors, to covering 4x5 at the range of magnifications you want.

You've mentioned DoF distortion a couple of times. What is it? The concept is new to me.

Re framing and focusing. Get a lens that will focus to, say, 20:1. Doesn't have to be a good one. Set it up on your TK. Focus, frame, etc. Close the shutter -- with the good lenses one always shoots wide open so you won't stop down -- insert a film holder, remove it, open the shutter. Don't shoot, and the film holder can be empty. Then check to see whether you've lost your original framing and focus. Share your findings with us. If you haven't done this experiment you don't know ...

vizion
20-Feb-2011, 10:46
Your focus on lenses is silly.

The focus of my question is on lenses but many respondents mistakenly assume I am not thinking of other things. One question one subject is my guideline otherwise - because everything in photography is inter-related the dialogue goes where people want to take you rather than giving you the information you seek. You are not the first person to incorrectly assume I havent read or understood the material to which you refer!





At the magnifications you want to work at (still not stated clearly) there's one sleeper, the 55/2.8 MicroNikkor AI/AIS. Reversed and shot at f/4 it is competitive with the 63 Luminar at f/4.5. Posters on the French LF forum insist that the 55/3.5 MicroNikkor is even better but I don't know whether they've done the comparison or simply found the f/3.5 good. I have both, have never tested the f/3.5. The f/2.8 is good enough.

The 55 MicroNikkors aren't significantly better (or worse) than comparable lenses from other makers so I suspect their competitors would be equally usable reversed above 1:1. Subject, for all including the MicroNikkors, to covering 4x5 at the range of magnifications you want.


That is interesting - thank you for sharing with me your personal experience. This is the type of response I wanted.



You've mentioned DoF distortion a couple of times. What is it? The concept is new to me.



I find different lenses of the same focal length differ in the degree to which the proportions of the part of the subject closest to the lens (and within the depth of field) is increased in apparent size by comparison with the part farthest away (and within the depth of field). Whilst the difference is quite small in macro work the significance of this difference is out of all proportion to its size.




Re framing and focusing. Get a lens that will focus to, say, 20:1. Doesn't have to be a good one. Set it up on your TK. Focus, frame, etc. Close the shutter -- with the good lenses one always shoots wide open so you won't stop down -- insert a film holder, remove it, open the shutter. Don't shoot, and the film holder can be empty. Then check to see whether you've lost your original framing and focus. Share your findings with us. If you haven't done this experiment you don't know ...
[/QUOTE]

I did that with and without the stabilisation bar that forms part of my bellows extension system. Without it there is some loss of framing & focus. With my stabilisation bar there is no loss of either framing or focus. My stabilisation bar is far more substantial & rigid than linhof's own tele/macro bracket. I am quite satisfied with that part of the system. I am still limited to the 20" of the TK's standard bellows extension until 7" extension is finished.

Thanks for your input - it is appreciated.

pdmoylan
20-Feb-2011, 11:46
David, I hope you are using a digital back because the amount of film you will use under these conditions before you obtain an aesthetically pleasing image where you have constant movement would, for me in any event, be monitarily wasteful. You also have to calibrate manual flashes, both primary and slave, on subject and background, so that your exposures are on. If you have a predetermined pattern of movement across the film plane, which would seem unlikely, or a series of infrared trip lights your success rate will increase; nonetheless, you will have to keep exacting records of aperture/shutter speed and distances/position/angles of flashes to the subject to perfect final images. And of course it takes time to have the film processed and returned and then you have to evaluate it vis-a-vis your records (I'm assuming you are shooting color). A clear issue for you is keeping track of the exposure and flash distance calculations, angles etc for each sheet. With roll film this is less of a problem since you have an uninterrupted series.

I do not envy you taking on this project but I respect your desire to experiment.

BTW, as with Dan, I have the Nikkor 50mm F2.8 micro and can attest to it's value reversed for > 1/1 magnification. But I have not employed it for greater than say 3/1, so Dan's suggestion to calculate your magnification is critical as that will determine which lens is right for you. You should however consider the Olympus 38mm lens as I believe it pushes up to 20/1. OLYMPUS has several now discontinued macro series that are touted very well with excellent color characteristics. Nikon, Zeiss, and Leitz all produced lenses for this purpose as well. They all must be used within 2 stops from wide open aperture to obtain maximum sharpness. Finding one of these specialized lenses may be the biggest challenge. Others have suggested reversing an enlarging lens for jewelry and this may be another avenue for you to consider.

Good luck and keep us informed of your progress.

Dan Fromm
20-Feb-2011, 13:04
pd, I've tested all five Luminars. They all lose sharpness when stopped down at all. Whether the small gain in DoF from stopping down a little is worth the loss of sharpness in the plane of best focus is a decision for the user. At higher magnifications stopping down is all loss.

pd, I've tested my 55/2.8 up to 5:1. It is competitive with the 63 Luminar and, given prices, perhaps the better choice for those of us with limited budgets. I find the Luminar easier to use, though, mainly because it is slimmer.

David wrote:
I find different lenses of the same focal length differ in the degree to which the proportions of the part of the subject closest to the lens (and within the depth of field) is increased in apparent size by comparison with the part farthest away (and within the depth of field). Whilst the difference is quite small in macro work the significance of this difference is out of all proportion to its size.

Thanks for the explanation. I've never seen the effect. Never. And I've shot lenses of the same focal length against each other at the same magnifications.

David wrote:
The focus of my question is on lenses but many respondents mistakenly assume I am not thinking of other things.

I should have been clearer. If you get a good grade of lens designed to work above 1:1 and use it within its designed range of magnifications it doesn't matter which one you have. They're all diffraction limited, low distortion, ... That's why I think your interest in lenses is silly. Just get the appropriate Luminar or Macro Nikkor or Photar and don't look back. Mikrotars can be good too, but in my and my friends' experience used ones are variable in quality; I blame this on their previous owners, not on CZJ.

vizion
20-Feb-2011, 14:18
That's why I think your interest in lenses is silly.

I have tried to be generous but to be honest I find such language arrogant!

Dan Fromm
20-Feb-2011, 14:49
I have tried to be generous but to be honest I find such language arrogant!

Excessively blunt, not overbearing. If I had intended to tell you to shut up and go away I'd have told you that as directly as possible.

There are many popular delusions. One that often surfaces here is that it really makes a difference which first-class lens -- there are many first-class lenses for most combinations of focal length, maximum aperture, and coverage -- is used. In my experience, attention to technique is much more important than which first-class lens is used. Bottom-of-the-barrel lenses are another matter entirely.

For an account of my experience with macro lenses, go here: http://www.galerie-photo.com/1-lens-6x9-dan-fromm.html If it isn't clear, I obtained and tried all of those lenses because I didn't believe most of the blather written about them. I wanted to see for myself which ones I could use to make a functional equivalent of a Wild Photomakroscope. Now I know. Profit from my efforts.

In high-magnification photography, no lens will save the photographer whose technique isn't meticulous.

vizion
20-Feb-2011, 15:33
Excessively blunt, not overbearing. If I had intended to tell you to shut up and go away I'd have told you that as directly as possible.
You probably would have done and I would have given you short thrift


There are many popular delusions. One that often surfaces here is that it really makes a difference which first-class lens -- there are many first-class lenses for most combinations of focal length, maximum aperture, and coverage -- is used. In my experience, attention to technique is much more important than which first-class lens is used.
Here I agree with your analysis but you had the arrogance to assume I could not possibly have sufficient experience to know that.. despite having been an active photographer for probably more years than you have been alive




Now I know. Profit from my efforts.
IMHO this is another demonstration of self satisfied and over weaning arrogant language. I am sure you do not intend to sound so smug but really!!!

Dan Fromm
20-Feb-2011, 16:41
David, please tell us about your experience. I was impressed by your having a TK, even more by your having made bracing that works. Having a big expensive digital Canon counts for something too.

That you persist in asking what seem like beginners' questions is puzzling. If you know as much as you want us to think, you have nothing to learn from anyone here.

Now, about your problem. You harp on lenses. If you knew which lenses would do the job you wouldn't have asked. You must not know. If you knew the relationship between focal length, magnification, and extension you wouldn't have asked the questions you did and you wouldn't be thinking of getting an extension tube for your TK. Again, you must not know or you must not be telling us enough.

You say its incorrect of me to conclude that you don't know enough about how to reach your goal of photographing bees and their parasites at fairly high magnification. You might well be right. Since you say you do, you are right. That doesn't help me understand why you persist in asking questions whose answers you already know.

Smug? Probably not. Stiff-necked, yes. Annoyed? Absolutely.

Cheers,

Dan

vizion
21-Feb-2011, 03:03
David, please tell us about your experience.

Apart from well over 60 years of image making ranging from wet plate to advanced digital techniques & much experimentation {including cracking the problem of how to shoot hdr images which include moving subjects (for which I was honoured by the RPS)) probably not very much that would interest you. I am a project photographer dedicated to experimentation and pushing the boundaries.

But can you not answer a simple question without needing to hold an opinion about either the person who poses it or their rationale for asking it?



I was impressed by your having a TK, even more by your having made bracing that works. Having a big expensive digital Canon counts for something too.

Fine but all these considerations are not pertinent when you are answering a simple question. It seems you have cultured an inner reluctance to assume that others are not entitled to ask questions unless you feel able to approve both their methodology and logic. If they fail that test I wonder why you give the appearance of feeling entitled to denigrate their endeavours.



That you persist in asking what seem like beginners' questions is puzzling.

If you understood the socratic method it would not be. What I have learnt in photography is that there are many many people who think they know it all. The consequence is that if say why you are asking a question they try and impress you with all their theories (the good and the half-baked) rather than concentrate upon providing the information you ask for. The only way to get useful information is ask deceptively simple open questions and hope there are a few people out there who will answer them.



If you know as much as you want us to think, you have nothing to learn from anyone here.
I have no need for you to think anything about me - I am not really that egotistical - I just get on with my own thing and am either dissappointed or delighted with the outcome. That is all I need. I need to say I wonder if you have a need to project your own attitude onto others. All I want people to do is, if they are willing, to answer questions I put; do me the courtesy of trusting I am asking them for a good reason and will put the answers to good use.



Now, about your problem.
I didn't pose a problem I just put a question!



You harp on lenses.
I have not harped -I leave that to the angels<grinz> and hope to avoid perjorative expressions myself- I have simply submitted a simple open question aski8ng people to share their experience with different lenses for macro on 4x5. It is you that dwelling on the false assumption I must be asking the wrong question even though you have, on your own admission, no understanding of why I asked it!



If you knew which lenses would do the job you wouldn't have asked.

I can see where you are coming from - but my suggestion is that you lack imagination about the ability of others to formulate questions where appropriate responses may help them to identify tests where the results may have a potential to push the potentials of our medium.



You must not know.
This is where assuming too much leads you into error.


If you knew the relationship between focal length, magnification, and extension you wouldn't have asked the questions you did and you wouldn't be thinking of getting an extension tube for your TK. Again, you must not know or you must not be telling us enough.
You are frustrated because you cannot guess why I am asking the question. I have no obligation to tell you and the reason I am not telling you is y because you, and maybe others, will be unable to answer it without that knowledge influencing the responses.


You say its incorrect of me to conclude that you don't know enough about how to reach your goal of photographing bees and their parasites at fairly high magnification. You might well be right. Since you say you do, you are right. That doesn't help me understand why you persist in asking questions whose answers you already know.
You assume the subject of the photography is my goal. Whilst I can understand the mental jumps your conclusions are both incorrect and simplistic. In my defence I would mention my experience with research has inclined me to the view that open questions best reveal information which is subjective and lies beyond simple measurable outcomes.



Smug? Probably not.
It seems to me that way!



Stiff-necked, yes.
I felt arrogant might be more appropriate <chuckles>



Annoyed? Absolutely.

My reaction is you need to be annoyed a little more frequently if you are going to appreciate the innate humility which IMHO forms part of our mutual genetic heritage.

I would add:
Humour & gentleness - possibly but pretty well hidden!


Take care

David

vizion
21-Feb-2011, 03:54
David, I hope you are using a digital back because the amount of film you will use under these conditions before you obtain an aesthetically pleasing image where you have constant movement would, for me in any event, be monitarily wasteful.
Well I use the canon 5D as a quasi back with my own adapter that places its sensor on the same plane as the GG screen. Even better is my laptop monitoring system which not only shows the GG screen but also corrects the image for viewing. This works well but is still a bit too Heath Robinsonian at the moment.

When the film is in place I monitor the subject with a videocam connected to the laptop and operate the shutter remotely.




You also have to calibrate manual flashes, both primary and slave, on subject and background, so that your exposures are on. If you have a predetermined pattern of movement across the film plane, which would seem unlikely, or a series of infrared trip lights your success rate will increase; nonetheless, you will have to keep exacting records of aperture/shutter speed and distances/position/angles of flashes to the subject to perfect final images. ....A clear issue for you is keeping track of the exposure and flash distance calculations, angles etc for each sheet. With roll film this is less of a problem since you have an uninterrupted series.

Well I pre-number my sheets when I load them using a cutter which puts a binary number onto each sheet using a series of nicks on the leading edge of the film. The same number is printed in large letters (a)on a label stuck to the cut film holder and (b) on my record sheets. (When hooked up to the laptop the notes go straight into the database.)



And of course it takes time to have the film processed and returned and then you have to evaluate it vis-a-vis your records (I'm assuming you are shooting color).

I have just built a new studio in my backgarden which has a new darkroom attached. I am lucky enough to have my own Colenta system which automatically processes 20 5x4 sheets at a time. So the processing problem is no problem!



I do not envy you taking on this project but I respect your desire to experiment.

Thanks I appreciate your support



BTW, as with Dan, I have the Nikkor 50mm F2.8 micro and can attest to it's value reversed for > 1/1 magnification. But I have not employed it for greater than say 3/1, so Dan's suggestion to calculate your magnification is critical as that will determine which lens is right for you. You should however consider the Olympus 38mm lens as I believe it pushes up to 20/1. OLYMPUS has several now discontinued macro series that are touted very well with excellent color characteristics. Nikon, Zeiss, and Leitz all produced lenses for this purpose as well. They all must be used within 2 stops from wide open aperture to obtain maximum sharpness. Finding one of these specialized lenses may be the biggest challenge. Others have suggested reversing an enlarging lens for jewelry and this may be another avenue for you to consider.

Helpful comments - incidentally have you noticed any differences in these lenses regarding what I call DOF distortion?



Good luck and keep us informed of your progress.

Thanks

David

Bob Salomon
21-Feb-2011, 06:24
"DOF distortion"

What is this?

vizion
21-Feb-2011, 07:24
"DOF distortion"

What is this?
The best way I can explain my tentative grasp of what I believe to be an actual phenomena is as follows:

It is the term I give to any percieved differential in apparent size of the closest and furthest parts of an image that lie within the depth of field of a lens that cannot be accounted for just by the difference in the angle of view.

I am quite curious about why some lenses of the same focal length, focused at the same distance with the same aperture appear to markedly differ in this respect. I cannot be certain whether differences in apparent size are just due to local adaption within the viewer's visual cortex and/or physical characteristics of individual lenses.

i.e is it all in the mind and the way it interprets an image or is it something which can be physically controlled either by lens design and/or other optical adjustments.
David

Dan Fromm
21-Feb-2011, 08:17
Which lenses show the effect and at what magnifications?

I ask for two reasons. It would be helpful to try to reproduce the effect. And at magnifications above 1:1 depth of field is very thin, so I have to wonder what can vary across it.

Bob Salomon
21-Feb-2011, 08:19
You seem to be describing foreshortening and that is focal length dependant. Perhaps what is causing this to your eye is that the marked focal length on any lens is only the nominal focal length. If you have 3 identical lenses from the same manufacturer with successive serial numbers no two will be exactly the same focal length. But the minute differences in focal length would not result in any difference as you see it. But the difference in focal length from two different manufacturers of the same focal length lens may account for it.

But even more likely would be the comparison between a true macro lens and another non macro lens.

What type of lenses were you using to experience the problem you refered to?

aduncanson
21-Feb-2011, 09:35
Fascinating. In the realm of 10X magnifications where propose to work, the depth of field (by the conventional CoC = Negative Diagonal/1800 criteria) is on the order of 0.11mm. (Makes wonder just how "exactly" you can lure or manipulate your live subjects to the desired focus point.) Even at the small working distance provided by a 50mm lens, your subject distance is something like 500 times the depth of field. In that respect it would be like making a portrait from 80 feet. I would not expect the one or two percent or so variation in focal length/working distance from one lens design to another to make a perceivable difference in perspective over that slim a depth of field.

vizion
21-Feb-2011, 10:04
You seem to be describing foreshortening and that is focal length dependant.
I agree foreshortening is a contributing factor but my visual experience inclines me towards the notion there is more to it. Foreshortening should be explained by angle of view alone. That is what "should" be the case but I am uncertain whether what "should" be is solely what actually occurs. I cannot prove whether my perception is accurate or inaccurate but I aim to try to test it.


Perhaps what is causing this to your eye is that the marked focal length on any lens is only the nominal focal length. If you have 3 identical lenses from the same manufacturer with successive serial numbers no two will be exactly the same focal length.
I agree this is a factor but I would ask is there evidence which conclusively demonstrates it is the only factor?



But the minute differences in focal length would not result in any difference as you see it. But the difference in focal length from two different manufacturers of the same focal length lens may account for it.

If foreshortening alone was the cause then lenses from two different manufacturers of exactly the same focal lengths "should" demonstrate an identical degree of foreshortening.


But even more likely would be the comparison between a true macro lens and another non macro lens.
I agree lens type may be a factor which does tend to muddy the water somewhat and make it more difficult to determine what, if anything, is going on.


What type of lenses were you using to experience the problem you refered to?

What made me sit up a few years back was two "identical" lenses I had for my pentax 6x7 kit. Both same year of manufacture. Both used on the same occasion, shooting the same subject but on two "identical" bodies. I finished the roll of film on the first camera and switched the second camera onto the first cameras tripod and shot using identical settings. When I processed the film the subject (a damsel fly shot at an angle of approximately 15 degrees to the film plane) had a noticeably greater depth of field on one roll of film. At the time I just put it down to inconstent management on my part. However I took the precaution of having both lenses and cameras professionally overhauled and checked.

I followed this up with a check in the studio using a long wooden rod painted with white marks at fixed intervals. This showed similar result. I had other things to do and forgot about it but from then on tended to favour one of the lenses.

I never saw similar results on macro work using 35mm but did see some similar discrepancies on MF. Now I am turning my attention to macro on 5x4 and thought ah well while I am doing the project I am currently engaged upon I will satisfy my curiosity and get a bit scientific about it. So my original questions was a fishing expedition to see if anyone would comment in detail upon the differences they have found between lenses.

vizion
21-Feb-2011, 10:23
Fascinating. In the realm of 10X magnifications where propose to work, the depth of field (by the conventional CoC = Negative Diagonal/1800 criteria) is on the order of 0.11mm. (Makes wonder just how "exactly" you can lure or manipulate your live subjects to the desired focus point.)
That is why I chose my bees - you can (if you know how) repeatedly get a series of bees tongues to precisely the same spot time and time again.



Even at the small working distance provided by a 50mm lens, your subject distance is something like 500 times the depth of field. In that respect it would be like making a portrait from 80 feet. I would not expect the one or two percent or so variation in focal length/working distance from one lens design to another to make a perceivable difference in perspective over that slim a depth of field.

Such a difference - (if it does exist) is of an as yet to be measured differential but at these magnifications the benefit of any gain (or disadvantage of loss) may be crucial.

Dan Fromm
21-Feb-2011, 10:54
<snip>

I followed this up with a check in the studio using a long wooden rod painted with white marks at fixed intervals. This showed similar result. I had other things to do and forgot about it but from then on tended to favour one of the lenses.

<snip>This is very surprising. Are you sure that both lenses gave the same magnification? And, if you shot the rod with negative film are you sure that negatives from the two lenses are equally dense?

I asked the second question because if the two lenses' focal lengths are close -- they should be -- then the one that gave less DoF may have a somewhat lazy stop-down mechanism. Not likely given you had them checked, but still the most likely cause. If you shot reversal film when testing with the rod then the effect of one of the lenses not stopping down to the aperture selected should have been visible.

Please tell us more about the similar discrepancies you saw with other MF lenses.

And do explain again what you mean by "DoF distortion." I ask because the behavior of the two P67 lenses you described doesn't seem to conform to the explanations you've given.

vizion
21-Feb-2011, 11:24
This is very surprising. Are you sure that both lenses gave the same magnification? And, if you shot the rod with negative film are you sure that negatives from the two lenses are equally dense?
Absolutely



I asked the second question because if the two lenses' focal lengths are close -- they should be -- then the one that gave less DoF may have a somewhat lazy stop-down mechanism.

Both lenses were at maximum aperture



Please tell us more about the similar discrepancies you saw with other MF lenses.

Sometime later I had something similar happen when using extension tubes on my Mamiya RZ67 kit. On that occasion I did not check as rigidly as happened with the pentax incident because I was travelling on a commission. So lacked the time to follow up. Just stuck in my mind but never done anything about it.



And do explain again what you mean by "DoF distortion." I ask because the behavior of the two P67 lenses you described doesn't seem to conform to the explanations you've given.

Well DoF distortion is just a convenient label I have given to the phenomena (but with a lack of certainty that its presence may be proven). In theory one should be able - from the angle of view to calculate how much bigger/smaller identical sized objects will appear to be when placed within the depth of field. DoF distortion is a shorthand term which I would apply when there is a lack of consistent size graduation within the DoF. What I noticed with the Pentax kit was the image with the greater depth of field demonstrated a proportionate consistency in the distance between segments which was not present in the other image - yet the total overall length of the damsel fly was for all intents and purposes identical. This was the observation that made the occasion memorable.

My first thought was that there was some lens curvature issue but as the segments were to the right and there was no corresponding effect to the left I continued to wonder what lay behind it.

So as part of my project I am going to do some tests and if something comes of it I will let you guys know.
David

pdmoylan
21-Feb-2011, 13:08
You know David, a slight lens misalignment or a very slight mis-focus resulting from either human error, less than tight connection between the camera mount and the lens mount, or a slight looseness in the focus grip on a lens might account for the DOF anomoly. When photographing wide open at high magnification, even the slightest difference in POF could give an appearance of more or less DOF. I have an old 400mm MF lens with IF which has a bit of "slippage" when focusing. It accounts for slight misfocus from time to time. When this occurs, there is an appearance of less than adequate DOF because I am photographing slightly behind the subject (typically).

It would be useful to see the dragonfly images you refer to for comparision.

Also, are you using your Canon to control the flash output on the subject?

Would love to see a diagram of your set up including the digital connections. It would be very instructive.

vizion
22-Feb-2011, 03:46
You know David, a slight lens misalignment or a very slight mis-focus resulting from either human error, less than tight connection between the camera mount and the lens mount, or a slight looseness in the focus grip on a lens might account for the DOF anomoly. When photographing wide open at high magnification, even the slightest difference in POF could give an appearance of more or less DOF. I have an old 400mm MF lens with IF which has a bit of "slippage" when focusing. It accounts for slight misfocus from time to time. When this occurs, there is an appearance of less than adequate DOF because I am photographing slightly behind the subject (typically).
I agree with everything you say which is why I describe my approach as "tentative". I do believe there is something going on but far from convinced! I am also, given the way in which our eyes work, it could simply be due to local adaption. The maximum diameter of the cam depends upon the amount of "throw" needed to move the plunger of your firmly mounted cable the required distance.



It would be useful to see the dragonfly images you refer to for comparision.

Most of my older stuff is packed in boxes whilst the new studio is being built. By the time the new storage units are completed I hope to have some strict testing done which will either prove my conviction is just plain nutty or there is something in it!



Also, are you using your Canon to control the flash output on the subject?

Both the TK and the Canon are equipped with wireless transmitters to trigger flash. However I prefer using multiple daylight reflectors or, when it comes to extreme macro, I like fibre optic lighting . Fibre optics give much finer control of lighting and are easy to custom build by robbing a few of the gruesome lighting displays obtainable quite cheaply from home decor stores.[/QUOTE]


Would love to see a diagram of your set up including the digital connections. It would be very instructive.
I am planning to make that available when I have tested the new design incorporating the bellows extension system with built in electronic connections for Canon and Nikon backs. My Heath Robinsonian (i.e proof of concept stage) remote copal shutter operating system is very simple - just uses a relay connected to an RS232 port to drive a 360 degree rotation of a cam (by a 12 volt stepping motor) to operate a standard cable release. I have two cams. One cut for timed exposures that increases diameter until the shutter is triggered at approx 120 degrees of rotation and then drops off at 180 degrees to relax pressure to enable the cable release to spring back. The other cam is for "bulb" which trigger at 120 degrees but continues to hold at 360 degrees until the current is cut when the cam is moved by a spring to a detent position at 5 degrees ready for the next cycle.

My original stepping motor system for both aperture & exposure control does not always work. It is far too Heath Robinsonian. I have designed what I hope will prove to be a production grade system and will let you have details when it has been built and tested & I am confident it works reliably (target date 2nd week of May). The objective is to integrate it into the extension system with a usb interface.

I want to say that I only like to develop gadgets when I feel they can help me achieve photographic goals! Sometimes I like to work with point & click cameras as well <chuckles>.

David

Dan Fromm
22-Feb-2011, 05:19
Both the TK and the Canon are equipped with wireless transmitters to trigger flash. However I prefer using multiple daylight reflectors or, when it comes to extreme macro, I like fibre optic lighting . Fibre optics give much finer control of lighting and are easy to custom build by robbing a few of the gruesome lighting displays obtainable quite cheaply from home decor stores.

Interesting. Tastes differ. Still and all your preference for continuous illumination surprises me a little and probably strongly reflects your choice of subjects and setups.

Please tell us more about your practice. I'm especially interested in how you shoot dragonflies and the like. I know that they often tolerate close approach but am not confident that they'll put up with having fiber optic cables stuck in their faces or being hemmed in by reflectors. With preserved specimens on pins, yes of course.

I've found standard fiber optic illuminators for low magnification microscopy useful with, e.g., the Photomakroscopes I sometimes borrow the use of to shoot preserved specimens. Small fish, rarely at magnifications > 5:1. Believe it or not, with preserved specimens and long exposures subject movement can be a problem. This because the specimens are usually shot submerged in ethanol to eliminate specular reflections from their surfaces. I sometimes hold them in position with self-closing forceps, put weights on them, ...; not practical with live specimens.

But with live subjects (fish, insects, flowers) I've found electronic flash preferable to continuous illumination because of its ability to stop motion. With insects, e.g., dragon flies, butterflies, that are perched on really solid supports subject motion isn't much of a problem but otherwise they, um, blow in the wind. How do you deal with this?


My original stepping motor system for both aperture & exposure control does not always work.

I appreciate the joy of, um, invention and doing things oneself. For me, though, inventing can get in the way of shooting. And where's the gain from reinventing the Prontor Professional or Sinar shutter systems? I must be missing something.

vizion
22-Feb-2011, 08:04
Interesting. Tastes differ. Still and all your preference for continuous illumination surprises me a little and probably strongly reflects your choice of subjects and setups.

Please tell us more about your practice. I'm especially interested in how you shoot dragonflies and the like.
Thanks for coming back to me. Sorry gave the wrong impression. I only tend to use contimuous lighting in confined quarters. Bee hives are one example!
Dragon & damsel flies in the open I look for slightly overcast days when the light is steady but not too dull. I do not like flash but prefer natural light, reflectors and fast lenses.


I know that they often tolerate close approach but am not confident that they'll put up with having fiber optic cables stuck in their faces or being hemmed in by reflectors.
Maybe I have been lucky but have found that Bees and most other insects that I can get into close quarter seem to have no objection to fibre optic lighting. Like you I think fibre optics are not practiacl in the field. Hoqwever I have found small led kits with minature reflectors very useful.


With preserved specimens on pins, yes of course.
Not my bag!


I've found standard fiber optic illuminators for low magnification microscopy useful with, e.g., the Photomakroscopes I sometimes borrow the use of to shoot preserved specimens. Small fish, rarely at magnifications > 5:1. Believe it or not, with preserved specimens and long exposures subject movement can be a problem. This because the specimens are usually shot submerged in ethanol to eliminate specular reflections from their surfaces. I sometimes hold them in position with self-closing forceps, put weights on them, ...; not practical with live specimens.

Something I have never done -- I seem to like things to be alive!



But with live subjects (fish, insects, flowers) I've found electronic flash preferable to continuous illumination because of its ability to stop motion. With insects, e.g., dragon flies, butterflies, that are perched on really solid supports subject motion isn't much of a problem but otherwise they, um, blow in the wind. How do you deal with this?

Interesting -- I usually try to capture an amount of motion that gives more information about activity - so I tend to avoid flash because I want to show motion<chuckles>.. guess you pays your money and takes your choice. Whatever takes your bag!



I appreciate the joy of, um, invention and doing things oneself. For me, though, inventing can get in the way of shooting. And where's the gain from reinventing the Prontor Professional or Sinar shutter systems? I must be missing something.

I am seeking to integrate remote monitoring (view & metering), control of shutter apperture, exposure, focus, lighting sound & recordkeeping from a laptop. I want a common system I can initially use for both 5x4 and slr digital cameras. This means tools that not only operate devices but also feed back current status via some form of communication system e.g usb, video

It may take me another year before I have everything working to a beta standard but I am hoping to be able to use individual modules before the third quarter of this year.

David

Neal Chaves
23-Feb-2011, 11:28
I photographed many stamps and coins at 1:1 on 4X5 with a 65mm f8 Super Angulon and a 58mm 5.6 Rodenstock Grandagon. I don't see how the results could have been any better and the client was very pleased. Since you are only using the center of the lens at this close focus distance, an inexpensive Grandagon with the typical edge separation could be an economical solution.

Brian K
23-Feb-2011, 17:08
I own the 180mm Makro Sironar, and find it to be a superb lens for macro work. However you mention that the insect is 2.5mm in size. That's really small and I would think that you'd want to go greater than 1:1.

You mentioned that you were using an enlarging lens mounted on a shutter. I've used that type of set up before for shooting the rounded individual bristle edge of a Crest toothbrush, we're talking something really small here. I ended up using an enlarging lens, and a lot of bellows and I used strobes. Did you turn your enlarging lens around? That is the negative side of the lens facing the subject and the print paper side of the lens facing the film?

I have to say though that unless you keep the repro ratio at 1:1 you're going to make it harder on yourself to shoot this. I don't know all the details of what you are planning, but just with the general information I'd most likely shoot it 35mm or MF using macros. In any case I wish you luck.

vizion
26-Feb-2011, 04:39
I own the 180mm Makro Sironar, and find it to be a superb lens for macro work. However you mention that the insect is 2.5mm in size. That's really small and I would think that you'd want to go greater than 1:1.

Agreed. The 2.5mm insect is adult pest that infests bees. Normally I would want to show active it on the bee so I am not expecting the parasite to occupy 75% of the film width but I do want the greatest enlargement that I can get.



You mentioned that you were using an enlarging lens mounted on a shutter. I've used that type of set up before for shooting the rounded individual bristle edge of a Crest toothbrush, we're talking something really small here. I ended up using an enlarging lens, and a lot of bellows and I used strobes. Did you turn your enlarging lens around? That is the negative side of the lens facing the subject and the print paper side of the lens facing the film?

Yes

I own the 180mm Makro Sironar, and find it to be a superb lens for macro work. However you mention that the insect is 2.5mm in size. That's really small and I would think that you'd want to go greater than 1:1.

Agreed. The 2.5mm insect is adult pest that infests bees. Normally I would want to show active it on the bee so I am not expecting the parasite to occupy 75% of the film width but I do want the greatest enlargement that I can get.



I have to say though that unless you keep the repro ratio at 1:1 you're going to make it harder on yourself to shoot this. I don't know all the details of what you are planning, but just with the general information I'd most likely shoot it 35mm or MF using macros. In any case I wish you luck.
I am always making things difficult for myself -- it seems to be what I do!!<chuckles>

I am looking forward to the time when we will have 5x4 full frame digital backs at reasonably economical prices. When that time comes I want to have designed tested & built and operated a 5x4 that can be managed (apart from its size) with the all the simplicity of a 35mm digital slr. Until that time comes I guess I will continue to make life difficult for myself!!

I intend to remain crazy<grinz>

Dan Fromm
26-Feb-2011, 06:52
David, now that we've agreed that we're all crazy I have a few more questions for you.

You've mentioned that you prefer to shoot with a large aperture and that you can tolerate, even prefer, some motion blur. Which lenses do you normally use, at what ranges of magnifications and apertures? And how much motion blur is too much?

I ask these questions because your practice differs considerably from mine. When working at lowish magnifications I typically shoot at somewhat too small apertures -- effective f/16 - f/32 -- rather than at larger apertures that would give better detail in the plane of best focus. And I can't abide motion blur.

Out and about with 35 mm I usually shoot no higher than 1:1, usually with a 105/2.8 MicroNikkor AIS. Normally with flash. In the lab, no higher than 5:1, usually with a wide-open Luminar, focal length selected to make extension manageable.

Out and about with a 2x3 Graphic I shoot between 1:8 and 2:1, usually with a 4"/5.6 Enlarging Pro Raptar, sometimes with a 100/6.3 Neupolar, both mounted normally. Normally with flash. The Wolly is very nearly symmetrical, when tested didn't benefit from being mounted reversed above 1:1. I have a flash rig for the Wolly that gives good exposure at f/16 set from around 5:1 to 2:1. No, not autoflash of some sort, geometry. To use other apertures I have to put more (or fewer) ND gels on the flashes.

I expect that the differences between your practice and mine flow from differences in preferences. No point discussing them. One personal comment that doesn't bear on preferences: I don't think you're lazy enough.

Cheers,

Dan

Dan Fromm
26-Feb-2011, 10:02
David, further thoughts. You have a 4x5 TK, are waiting for an affordable 4x5 sensor to come to market so you can use the TK as a digital SLR. Nice dream that I share even though such a digital SLR won't have auto diaphragm.

Have you considered modifying a 4x5 SLR such as a Graflex or Mentor or ... so that it will attach to y'r TK's rear standard? I ask because I have a 2x3 Graflex module for my 2x3 Super Cambo. Removed the Graflex' bellows and focusing mechanism, attached a cut-out Cambo board to its front.

I'm not sure that a TK is the best view camera for making a long rail SLR, could be mistaken. This because of the rail design. It turns out that my Graflex module rocks a little on the SC's carrier frame, has to be supported. The simple solution is a lab jack that sits on the rail. In your application this would use up roughly 6" of rail. I suppose there are other simple and inexpensive solutions; I replaced my SC's original rail with a length of 1" square t-slotted aluminum extrusion.

I haven't looked hard for long rail 4x5 SLRs, have seen long rail 2x3s (Arca Swiss, Makiflex) so suspect there are also long rail 4x5s.

vizion
26-Feb-2011, 11:43
David, further thoughts. You have a 4x5 TK, are waiting for an affordable 4x5 sensor to come to market so you can use the TK as a digital SLR. Nice dream that I share even though such a digital SLR won't have auto diaphragm.
I think I mentioned somehwere or other that I have been designing stepping motor applications for remote control of shutter, apperture & focus all linked to a laptop. The laptop will also be linked to exposure meter giving a sophisticated control system. I think the real challenge is view management. I am thinking a small video camera which mounts to a shoe on the 4x5 back. The laptop could be easily programmed to provide both parallex correction and, when fed with lens focus & aperture data, detailed DOF correction.



Have you considered modifying a 4x5 SLR such as a Graflex or Mentor or ... so that it will attach to y'r TK's rear standard? I ask because I have a 2x3 Graflex module for my 2x3 Super Cambo. Removed the Graflex' bellows and focusing mechanism, attached a cut-out Cambo board to its front.

I'm not sure that a TK is the best view camera for making a long rail SLR, could be mistaken. This because of the rail design.

I had exactly the same reservation until I came up with my extension modification which has now been extended to give up to a total of 40 inches of bellows. The base unit is machined out of a 1/2 inch (13mm) x 3inch (77mm) magnesium/aluminium alloy. The weight is substantially reduced & rigidity enhanced by using a stepped profile plus T section side frame. The front standard is supported throughout the movement range. I have just finished the design of a bellows to give up to 40" with a light weight intermediate support system.

Preliminary test with a mock up show the TK to be absolutely rigid at 20" even with heavy lenses. There is no reason why the rigidity should be any less at 40" because the extension beyond above 20" is achieved by backward movement of the rear standard which in theory adds additional stability due to increased counterbalancing. (The rear standard is adapted for this).



It turns out that my Graflex module rocks a little on the SC's carrier frame, has to be supported. The simple solution is a lab jack that sits on the rail. In your application this would use up roughly 6" of rail. I suppose there are other simple and inexpensive solutions; I replaced my SC's original rail with a length of 1" square t-slotted aluminum extrusion.

I do want to stick with 4x5



I haven't looked hard for long rail 4x5 SLRs, have seen long rail 2x3s (Arca Swiss, Makiflex) so suspect there are also long rail 4x5s.

IMHO the TK 45S is the gold standard as far as 4x5 is concerned but no-one has ever made something which cannot be enhanced!! When I am completely satisfied with all aspects of my designs I would like to feel they were good enough to be more widely used.

Dan Fromm
26-Feb-2011, 13:54
David, thanks for the reply.

I didn't mean to suggest that you replicate what I have, rather that you convert a 4x5 SLR such as a Graflex to an SLR module for your TK.

The SLR has an advantage over a conventional view camera. No delay between focusing, composing (or composing, focusing) and shooting because of the need to insert a film holder, close the leaf shutter, stop the leaf shutter down, and pull the dark slide.

Y'r devices can save the time needed to close the shutter and stop it down but I'm not clear on how they'll insert the film holder rapidly. Not to say that you haven't thought about how to do it, rather that you haven't shared your ideas.

vizion
27-Feb-2011, 02:09
David, thanks for the reply.

I didn't mean to suggest that you replicate what I have, rather that you convert a 4x5 SLR such as a Graflex to an SLR module for your TK.
It is a good idea however my experience led me to the conclusion that SLR is too bulky and inflexible for most 4x5 applications especially if a way could be found to automate film loading, shutter & aperture. You are right - I have not mentioned my approach to the film loading issue. Automating film loading and storage is a challenge but solvable. My first design was an abysmal failure because I could not get a roller feed system to work consistently without scratching the film. I am now experimenting with a new design which is surprisingly reliable even at the Heath Robinson stage. It has the virtue of simplicity and has potential to provide an automated film loading transport and storage system for 4x5. The system includes a replacement for the dark slide. The design incorporates a sheet identification system by an extension of a simple 8bit binary marker to provide a unique ID for each sheet.

For me one of biggest challenges of 4x5 is the conflict between the need to get the camera in an ideal location and one's body positioned to facilitate operation. I want to to automate & remotely control the camera so that the operator does not have to be in physical contact (after the camera has been placed on a tripod). A full system should include modules for tripod control of panning, tilt, yaw plus rise and fall of a central tripod column. The latter is the most challenging due to power requirements. One approach would be to use stepping motor control of counterbalanced column movements by a small compressed air cylinder compressing air on descent and driving the column for rise. All these controls can be achieved using a laptop interfaced with stepping motors. A modular approach is essential to provide incremental expansion of the system. I believe a feed back via software of the state of all devices form an essential ingredient in any potentially successful system. It also has to be designed so it can be transferred to 10x8.

Dan Fromm
27-Feb-2011, 07:20
David, thanks for the reply.

If you want the full range of view camera functions then attaching an SLR module to the rear standard can seem limiting. But since the SLR is attached to the rear standard instead of mounted directly on the rail it doesn't interfere with rear movements, which the standard provides. With relatively large movements, though, the box may vignette.

I didn't suggest that you use an SLR module for all purposes. It might, however, help you with photomacrography while you're stuck with film.

I keep forgetting to raise another point that's important for closeup work. People who shoot at high magnification set extension to get the desired magnification and then focus by moving the camera/lens assembly as a unit. That's why we use focusing rails. Do you plan to incorporate one in your 4x5 bee cam?

vizion
27-Feb-2011, 11:46
David, thanks for the reply.

If you want the full range of view camera functions then attaching an SLR module to the rear standard can seem limiting. But since the SLR is attached to the rear standard instead of mounted directly on the rail it doesn't interfere with rear movements, which the standard provides. With relatively large movements, though, the box may vignette.
Thank you again. You make a good point



I didn't suggest that you use an SLR module for all purposes. It might, however, help you with photomacrography while you're stuck with film.

Yep I guess a full frame 4x5 will be a long time coming (4 years or more).


I keep forgetting to raise another point that's important for closeup work. People who shoot at high magnification set extension to get the desired magnification and then focus by moving the camera/lens assembly as a unit. That's why we use focusing rails. Do you plan to incorporate one in your 4x5 bee cam?
Certainly -There are some additional possibilities. My inclination is to use a helicoil extension for fine focus as a final stage after bellows extension. Helicoils lend themselves to reasonably rapid action under stepping motor control & use less current than bellows. Additionally one could make automated bellows adjustment work faster for non macro work if fine macro focus uses such a separate mechanism.

Returning to your suggestion of whole body adjustment, there are some real positives especially if counterbalancing was used to control weight distribution fore and aft of the tripod mount. This would reduce power demand and contribute to long extension stability. This could be provided by an additional module which bolted below the main extension and fitted to the tripod. This would invite one to consider adding a limited range of traverse movements to the option. Traverse range would be limited by the implications of the TK's portrait mode which moves the COG well off the tripod centre line.

The key to all of these ideas is providing a reliable remote focusing aid so I must concentrate on refining that system next.

Dan Fromm
27-Feb-2011, 13:00
My inclination is to use a helicoil extension for fine focus as a final stage after bellows extension.

I see the attraction, think it is a bad idea anyway. Suggest that you fiddle a bit with a crude prototype, doesn't have to be as advanced as Heath Robinson or Rube Goldberg would have made it, to see whether focusing by changing magnification works well enough in the range of magnifications you intend to use. If it works well enough, great!

In my experience, large translations at high magnification are problematic. The standard solution is crossed focusing rails for "touching up" and setting up all over again if the crossed rails won't get the composition wanted.

Re focusing aids, at high magnification there's little doubt where the plane of best focus is. Automatic focus detection is a nice idea, in my experience with 35 mm SLRs AF tends to pick the wrong plane of best focus when working closeup. Remote focus detection with the equivalent of a cine camera video tap seems very possible so I'd like to know how your trials with it work out.

vizion
28-Feb-2011, 03:01
I see the attraction, think it is a bad idea anyway.
Slightly confused - ambiguity about what you refer to as being "bad idea"


Suggest that you fiddle a bit with a crude prototype, doesn't have to be as advanced as Heath Robinson or Rube Goldberg would have made it, to see whether focusing by changing magnification works well enough in the range of magnifications you intend to use. If it works well enough, great!

Sensible


In my experience, large translations at high magnification are problematic. The standard solution is crossed focusing rails for "touching up" and setting up all over again if the crossed rails won't get the composition wanted.
Crossed rail automation may be a bit power hungry for 5x4 and may be altogether too much for 10x8 without a big power pack unless a low weight compressed air or hydraulic solution with counterbalancing is actually possible (I have my doubts!).


Re focusing aids, at high magnification there's little doubt where the plane of best focus is. Automatic focus detection is a nice idea, in my experience with 35 mm SLRs AF tends to pick the wrong plane of best focus when working closeup.
I am in total agreement


Remote focus detection with the equivalent of a cine camera video tap seems very possible so I'd like to know how your trials with it work out.

I will keep you informed. End of June is my target for a viable video monitoring system - provided my new studio build is complete by end March. I have completed a Heath Robinsonian test (for me Heath Robinsonian test suggests "proof of concept stage indicates project viable").

I think this is very do-able and has the benefit of offering vertical & horizontal correction by Software. Combined with software management of all camera movements this approach has the potential to completely change the management interface for LF cameras for the better. In the medium term it could lead to LF control by hand held devices such as cell phones, ipads & the like. Viewing control and automated film handling are essential bedrocks of a successful system.

Dan Fromm
28-Feb-2011, 04:01
Thanks for the reply, sorry for the lack of clarity.

I doubt that focusing by changing extension (y'r idea of using a helical for fine adjustments) is a good idea at high magnification, am glad that you agree that it should be tried out before going ahead.

Its an empirical question, but I think you're stuck with low-friction slides until proven otherwise. I understand y'r concerns re power consumption, have visions of an LF camera tethered to a motor-generator set.

vizion
28-Feb-2011, 07:10
Its an empirical question, but I think you're stuck with low-friction slides until proven otherwise. I understand y'r concerns re power consumption, have visions of an LF camera tethered to a motor-generator set.

That is my concern. Low friction slides only address the friction issue but does not affect even greater demands - namely the amount of energy required to overcome inertia especially any movement requiring energy to overcome gravity. Compressed air/hydraulics and counterbalancing designs are IMHO the only way to reduce those factors. Power consumption should ideally be limited to the level a reasonably compact solar powered battery unit can be expected to deliver. i.e constant solar charging during daylight hours providing sufficient energy for a reasonable amount of daily operation with commercial batteries backup seen as a reserve.

vizion
28-Feb-2011, 07:38
Thanks for the reply, sorry for the lack of clarity.

I doubt that focusing by changing extension (y'r idea of using a helical for fine adjustments) is a good idea at high magnification, am glad that you agree that it should be tried out before going ahead.
.
Actually your comment has given me a design idea which I am going to call "Compensatory Helical Adjustment for Large Format" [CHALF]. The concept requires the rear standard be designed as a unit separable from its mount and moveable upon it. Its application combines the use of adjustment of lens position by a helicoil mount with fore and aft adjustment of the rear standard using a fine helix screw. Both adjustments would be accomplished using stepping motors under laptop control. This means fine movements of both lens and rear standard are independent of track adjustment. This concept should, in theory, be capable of delivering greater focussing accuracy together with more rapid & accurate delivery of larger bellows movements and low energy consumption. Thank you.

aduncanson
28-Feb-2011, 09:26
Vizion,

I strongly recommend that you mount a short enlarging lens on your camera and start experimenting in the magnification range that you are considering. Or, just play around with the applicable equations: 1/F= 1/So +1/Si, So = (1+1/M)F and Si = (1+M)F.

At 10X, fine focus on the rear standard seems unlikely to be very helpful. When you move a 50mm lens forward on the helical mount by just 1/10th of a millimeter, it shortens the object distance by that amount, and the image distance then lengthens by 10mm. Just how much range do you expect to have on your rear standard fine focus mechanism? (By the way, I think that the kind of lead screw driven fine focus you describe is built into some Sinar standards. I have no detailed information on how those work.)

I was recently playing with a pair of Cambo monorail cameras ganged together to give me about 40 inches of rail and more than 30 inches of bellows. To get up to about 9x magnification I used an 80mm enlarging lens mounted backwards on the Cambo lens board. I used three of the Cambo standards and the two bellows to make up the camera and used the fourth standard as a subject stage. It was handily adjustable in position, pitch and yaw. Using north window light, I suffered exposures of about 5 seconds on HP5+ due to bellows factor and reciprocity failure. This while stopping my lens down only to f/5.6 to minimize diffraction. The whole rig was made up of off-the-shelf components and could be duplicated for about 500 USD today. Dan described replacing the Cambo rail with some type of square stock, which is probably desirable if only because it allows even longer extension.

Focusing was, of course, done by adjusting the position of the subject stage, and was a challenge because my arms are quite a bit shorter than was my rail. For cheap and dirty, a flexible extension shaft might help a lot. I can imagine that your subjects might not tolerate having their stage moved about to focus and hence Dan's suggestion of moving the camera as a whole seems attractive. But obviously that presents difficulties because of the mass of your rig.

The enlarging lens I employed was the well respected 80/4.0 Beseler HD reportedly identical to one of the recent Rodagons. The resulting negatives seemed pretty good when viewed through a loupe, but might not stand up to a high degree of enlargement. Dan reports that his Luminars, etc., are far superior to enlarging lenses in his experience and I have no reason to doubt him.

Best of luck - Alan

Dan Fromm
28-Feb-2011, 09:47
Alan, so you'll know, my shorter Luminars are better than any of the enlarging lenses I've tried. My 100/6.3 Luminar wasn't good at all, was much worse than a known good one I borrowed from Charlie Barringer. To his and my great surprise, a humble $12 4"/5.6 Enlarging Pro Raptar tested as good as his 100 Luminar from 1:8 to 4:1. I didn't test either at higher magnification. My 100/6.3 Neupolar was better still, a 90/6.3 CZJ Mikrotar that I eventually sold to Charlie was as good as the Luminar.

I use the Wolly much more often than the Neupolar because it is much easier to use. Part of this is that I often have trouble seeing the Neupolar's aperture setting in the field, part is that I can attach my wonder-working miraculous flash bracket to the Wolly but not to the Neupolar.

What's wonderful about the bracket? Simply that it gives good exposure from 1:5 to 2:1 with the same aperture set. Saves thinking.

In general, with these beasties the shorter the lens the sharper.

el french
27-Nov-2011, 15:46
I wonder how this turned out?