Lenses for macro on Linhof Tecknikardan

[vizion]

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]

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]

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]

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]

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]

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]

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]

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]

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]

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.