May Need Help

[bob carnie]

So I just got back from up north and tried for the second time in my life working with a Large Format Monorail Camera * cambo with 150mm lens*

Film is still to be processed but I wanted to post first so if this film is *genius level* then I do not want any doubting Thomas types slagging me , as trying to set you up.

It was just raining very flat light, I want to shoot a series of Pine trees that are along a path.
Now here is the problem , how do I keep the front tree , middle tree , and far tree in focus. Let alone standing straight, boy using these cameras is hard.
I figured out that the only thing I could do was to keep the camera level, trees straight and close the lens way , way down as well focus on the first tree .
I used the sunny f 16 method for metering which in my estimation was around 2 second at f32.5 to 6 sec f32.5. If I am off next purchase will be a light meter, but for now I will try to use brain calculations.

I will post my results tommorow or wed and would like the lens/largeformat/geek heads give a critique and possible suggestions where I went wrong.


Should I used swings , tilts , shimfugs, stand on my head, wider lens, longer lens, or should I just give up and keep printing.

So I will post images asap and get ready for wise advice.

[Daniel Stone]

hey Bob,

this was the same question that I had, and almost the same situation :)!

you might want to do some reading up on the "scheimpflug" principle, its very straight forward, and it allows creative freedom, or correction(depending on your vision for the photograph) to give you what you want.

http://en.wikipedia.org/wiki/Scheimpflug_principle

there's also pretty good video(albeit it deals with a studio subject, but the principle is the same as in the field), here it is:

http://www.youtube.com/watch?v=gR4m70xr9mE

cheers!

-Dan

[Vaughn]

Focus would normally be placed about 1/3 of the way into the scene that you want in focus. The DoF grows in both directions as you stop down (forwards and away from the plane of focus, but twice as fast away as forwards). So by focusing on the first tree, we'll just have to see if the last tree is in focus sufficiently for the size you want to print. If one is to err, you erred in the right direction. Out of focus backgrounds are easier to look at than out of focus foregrounds.

Probably, no tilt would have helped you. Standing on your head might have helped get blood to your brain.

No idea about your exposure -- depends too much on the film ASA, time of day and how much out in the open the scene was. Develop one neg and use the results to determine if you need to increase or decrease development time to increase or decrease (respectively) contrast for other similarily exposed negs.

Looking forward to the results!

Vaughn

[Pete Watkins]

Bob,
We are not "Geek heads".
We just know more than you.
If you are asking forum members for help or assistance and advice do not "take the piss" as we say in England. If you doubt that we are better than you watch the World Cup match on Saturday. That is "The World Cup" Football competition, not inferior imitations.
Good luck on Saturday, Ha, Ha, Ha.
Pete.

[bob carnie]

Ok

so I saw the film and the exposure was nothing short of brilliant.. Who said, I don't need no stikin lightmeter, what would happen if it broke.

So I am going to scan tonight and tommorow morning and put up an image for serious deliberation.... I do need you large format geek heads to help with the fineses.

What is the World Cup?? Is in not being finalized tommorow night in Philidelphia by one of the Original Six.

Bobby Hull is my hero

Bob

[Richard K.]

Now here is the problem , how do I keep the front tree , middle tree , and far tree in focus.

Hey Bob;

If the trees are behind each other in a line or alternating left and right sides there's no much yah ken doo, just stop down but I'd probably focus a little behind the first tree. If they're in a row but all to the left or all to the right then you can Scheimpflug a little and stop down.


Should I stand on my head, ....

If it can take the weight! Actually if you stand on your head the GG will have the scene right side up which may actually help you with that othe rproblem you're having... :D

[Richard K.]

Bobby Hull is my hero

Bob

I thought the greatest ever was your hero!.....Bobby...Orr!!!!!!! :D

[bob carnie]

Ya but Boston isn't playing so lets give some kudos to the Hull Brothers and son.


I thought the greatest ever was your hero!.....Bobby...Orr!!!!!!! :D

[bob carnie]

Ok Its eight pm, I got to the lab at 3. film has been processed , and low rez scan are done.
I am going home, but will post tommorow a couple of images, with a few thoughts and observation.

First off I am addicted to large film, impatience will cause major problems.

After 35 years of printing and some photography, the sunny f16 rule works like a dream,
I think my position of focus is off, as though the first tree is super sharp the trees in the background are not what I want.
I believe Richard and Vaughn are both correct , I now have to decide where that point of focus will be using the 1/3 2/3 rule of DOF but exactly where with confidence would I foucus, shit I need some polaroid.
As well I am beginning to think a wider lens will give me a greater depth of field. IE a 135mm or 90mm over the 150.
As Richard suggests there are trees on both sides , therefore closing down the lens is really the only option, I did go down to 32.5 on a minimum f45 lens.

This is lots of fun, but rather expensive to blow through all this film and conclude that I have to reshoot.

I will post images in the AM

[erie patsellis]

Bob,
as you've realized, processing and printing your own images causes one to become far more heavily invested emotionally. Good luck on your re-emergence... :)

[bob carnie]

Ok here are the images
Both show the same problem as I see it , which is unacceptable loss of sharpness beyond 4.

1- indicates closest tree*where I focused right down to 4 - furthest away.
150mmlens , at f32.5 3 three bannana exposure.

[Brian Ellis]

There isn't much camera movements could have done for you in that situation. You might have focused a little ways into the scene (not a third of the way since that "rule" varies with focal length of the lens and also because it isn't that easy in a landscape to know just where 1/3 is) instead of on the closest tree and then stopped down stopped down farther.

IMHO the best way to make sure everything that you want to appear sharp in the print actually appears sharp is to focus on the nearest object you want to appear sharp (tree #1 in your situation), note the position of the front or back standard (whichever you're using to focus), then focus on the farthest object you want to appear sharp (whichever tree beyond #4 you wanted to appear sharp), note the position of the focusing standard, then set the relevant standard half way between the two points and consult a depth of field table to determine the optimum aperture to use in order to obtain the depth of field you need. This is all explained better and in more detail in Tuan's article in this forum on focusing the view camera.

[Monty McCutchen]

Bob,

I have rulers on all my camera's beds (thin ones can be bought at fabric stores and taped, glued, whatever onto the bed railing of your camera) that allow me to note closest and farthest objects as Brian mentioned and then easily determined middle point with simple math off the ruler readings. I realize this method due to the simple math may be beyond you but you could bring an assistant, maybe Dinesh, with you for that purpose. But the most important thing to remember is to wear your helmet when you are out in public.

Monty

[Vaughn]

Hey, Bob, there is a thing called a ground glass on the back of the camera -- that will tell you (if you listen close enough) how much depth of field you have at any f/stop. Well, at least until f22 or so (then it gets a bit dark).

Focus, for example, on tree #3 of the second image. Then close the lens down as you keep an eye on the closest tree (#1). When it gets in sharp focus, note the f-stop. Open up the aperature again and repeat, looking at what f-stop the furthest point you want in focus becomes sharp. Both the near point and the far point should come into focus at about the same time. You then move your focus point until they do. That should be the best place to focus at and then close the lens down another stop (to compensate for our aging eyes) and you have a relatively sharp scene from front to back.

Just one way to do it. I am very near-sighted, so without my glasses I can focus my eyes 4" from the GG -- you might need a loupe.

Vaughn

[bob carnie]

Thanks for the replies so far, I now seem to recall the method Brian mentions.
It was a pretty dull day so I would need a brighter screen or better loop, it was raining and the loop kept steaming up.

Re Mr McCutchens response, I think I need to go to the thesauras so that I can ellucidate exactly my thoughts to him.

How about a wider lens , would this give me possibility of greater depth of field?

[Vaughn]

How about a wider lens , would this give me possibility of greater depth of field?

Yes and no. Depth of field will be affected by three things -- Focal length (longer lens, less DoF), aperature and distance focused (closer the focus, the less DoF). This all assumes same size enlargement from the same format size.

So with all things being equal, a 120mm lens will have a slightly greater DoF than a 150mm. But to get about same image as the 150mm, you will have to move the camera a little closer to the subject, reducing the DoF.

[bigdog]

How about a wider lens , would this give me possibility of greater depth of field?

Yes. I suggest a 50mm, mounted on a 35mm body. Stop down to f16 and it will all be in focus and sharp ... :D

[Frank Petronio]

There was a reason they called it the f/64 Group.

[Patrick Dixon]

There was a reason they called it the f/64 Group.

What was that then?

[Vaughn]

The f64 Group was organized in 1932 by Ansel Adams, Edward Weston, Willard Van Dyke, Imogen Cunningham, and others, to promote "straight" photography. The group was in response to the "artistic," soft-focus, pictorial type of photography which was popular at the time. Emphasis was placed on "pure" photography, sharp images, maximum depth-of-field, smooth glossy printing paper, emphasizing the unique qualities of the photographic process. The significance of the name lies in the fact that f/64 is the smallest aperture on the lens of a large-format camera and therefore provides the greatest depth-of-field.

Copied from: http://kcbx.net/~mhd/1intro/f64.htm

I think that was what you were asking...

Vaughn

[Robert Hughes]

The name for the pinhole camera group f295.org (http://f295.org) is a takeoff on that concept, as pinhole cameras have essentially infinite depth of field.

[John Powers]

Bob,

Monty mentioned rules from fabric stores. You can also get adhesive backed metal or mylar rules from Reid Supply Company www.reidsupply.com. I picked metric just for more increments. Dick Phillips was kind enough to screw these to either side of my 8x10 and 7x17.

You were generous to compliment me on going back to take eighteen college courses in photography in my retirement. Having seen you in your shop and at Bill’s, I know you to be a relaxed and patient man. The major benefit of those courses is a critique of ten new prints every two weeks. Practice, make mistakes, learn, practice, get feed back, make new mistakes, practice, burn film. Shoot B&W when you are learning. It is cheaper.

Isn’t Michael Smith offering a workshop soon?

John

[bob carnie]

John I will look into Reid Supply , thanks.

If I go back to school I think it will be a cooking school or better yet an english major course so that after four years, I will be able to debate with the esteemed Mr McCutchen and not be at a disadvantage. Actually it may take more than four years.

How is that system for lugging around your big camera? I was very tempted by Richard K thread about the big pano camera and was trying to get my head around, how to lug that thing around if I was able to purchase it.

I am not sure what M Smith is up too, I have not seen them since the first APUG conference.

Bob,

Monty mentioned rules from fabric stores. You can also get adhesive backed metal or mylar rules from Reid Supply Company www.reidsupply.com. I picked metric just for more increments. Dick Phillips was kind enough to screw these to either side of my 8x10 and 7x17.

You were generous to compliment me on going back to take eighteen college courses in photography in my retirement. Having seen you in your shop and at Bill’s, I know you to be a relaxed and patient man. The major benefit of those courses is a critique of ten new prints every two weeks. Practice, make mistakes, learn, practice, get feed back, make new mistakes, practice, burn film. Shoot B&W when you are learning. It is cheaper.

Isn’t Michael Smith offering a workshop soon?

John

[John Powers]

Bob,

”How is that system for lugging around your big camera?” It is great and would work well at least for his 8x20 which unfortunately is sold. The 14x17 might be too top heavy for the balance of this rig. A variation might be needed.

This is the model I use. http://babyjogger.com/perf_jogger_lp.aspx
A canvas bag of six 7x17 film holders is bungied to the bottom rail. It is a good place to carry them, and it also lowers the center of gravity of the camera-tripod. A 12x12 inch cooler bag of lenses, meter, loop, dark cloth sit in the baby’s seat. Throw away the hood. The camera mounted on a big Ries sits above the bag with the spikes through the foot pad and the head bungied to the shock absorbers. Works for me on trails and woods. It won’t do stairs or cliffs, but at 70 neither do I.

”I am not sure what M Smith is up too, I have not seen them since the first APUG conference.” The comment was a tease in reference to your expressed feelings at that time. There is no doubt in my mind that you will master the view camera. However it will take even your sharp mind more than two tries.

John

[bob carnie]

Thanks John

Going to give it a try again this weekend, with the new Ektar 100, lots of fun, and actually after years of Mamiya 7, Hasselblad, Fuji 6x9 and lately Pentax 6x7, the cambo rail camera is more to the way I like working, I just hate the setup envolved but I think over time it will be a piece of cake.


BTW Folks

I really appreciate all the help , the trees is a location that is very easy for me to go back too and reshoot, I plan to focus with the methods listed, I will stay with the same lens and close down to f45 its min apeture, going back end of month and if raining should be able to duplicate lighting conditions as there is a magnificent canopy supplied by these wonderful trees.
Wondering this, is there a 150mm lens that would have a smaller apeture that I should be considering, as I do like the normal view??
I will post my new versions after my next attempt for more critique.

thanks
Bob


Bob,

”How is that system for lugging around your big camera?” It is great and would work well at least for his 8x20 which unfortunately is sold. The 14x17 might be too top heavy for the balance of this rig. A variation might be needed.

This is the model I use. http://babyjogger.com/perf_jogger_lp.aspx
A canvas bag of six 7x17 film holders is bungied to the bottom rail. It is a good place to carry them, and it also lowers the center of gravity of the camera-tripod. A 12x12 inch cooler bag of lenses, meter, loop, dark cloth sit in the baby’s seat. Throw away the hood. The camera mounted on a big Ries sits above the bag with the spikes through the foot pad and the head bungied to the shock absorbers. Works for me on trails and woods. It won’t do stairs or cliffs, but at 70 neither do I.

”I am not sure what M Smith is up too, I have not seen them since the first APUG conference.” The comment was a tease in reference to your expressed feelings at that time. There is no doubt in my mind that you will master the view camera. However it will take even your sharp mind more than two tries.

John

[ki6mf]

I would get a Dept of Field Table for the focal length of your lens. Make sure it covers all your F stops. Then use that to estimate the distance you need to focus to get the coverage your want. A problem with Scheimpflug is that tall fore ground objects are not in focus as plane of focus is tilted and tall objects stick up through the plane of focus. Normal DOF : | | -|| With Scheimpflug : | \ -\|

[bob carnie]

Bumping a old thread.

So I am very happy with the 4x5 and 8x10 negatives I am producing. Please don't laugh.

I am working on a project that requires long bellows to get almost 1:1 size on film.
The size of objects are getting smaller and I need to figure out how to fill the frame on 4x5 and 8x10.

I am using a Cambo with a 210 lens for 4x5
I am using a Agfa Ansco on a Century semi stand 1 with a Voigtlander Braunscheig Helliar 1:4,5 f 48cm Lens for the 8x10 work.

To date the objects I am using fit nicely into the capabilitys of the optics I have.
How do I photograph smaller objects , about 1 inch in size , and place them to about 4inches on 4x5 or 8 inches on the old 8x10 camera.
Dino the Dinasor is about 4 inches tall and is pretty much maxing out my current setup. I have a wonderful collection of smaller objects and I am in trouble as I want the object to fill the frame in 4x5 and 8x10.

I really do not want to change gear as I like the equipment I am using , so how do I magnify objects... Kind of like the difficulty one has when reducing images on a enlarger.

Remember folks, I am new to large format cameras, so be gentle with your comments, working with these cameras are fun and I hope its only a matter of getting a couple of different lenses????

[erie patsellis]

Bob, the easiest way is with a shorter f.l. lens. If you're using strobes, consider borrowing some of your enlarging lenses.

[rdenney]

Remember folks, I am new to large format cameras, so be gentle with your comments, working with these cameras are fun and I hope its only a matter of getting a couple of different lenses????

Just use a shorter lens. 210 is pretty long for 4x5, and will require about 16" of bellows draw at 1:1. My quick calculation suggests that an 80mm lens will provide the 4:1 you are seeking with the same 16" of bellows draw. The subject will be 4" from the lens, rather than 16" from the lens as with 1:1, so you'll need to make sure the camera does not shade the subject.

Given that most lenses are optimized for 1:10 or more, I would mount the lens backwards in the shutter--rear cell in the front and front cell in the rear--to turn that optimization around. That will get it a lot closer to the 4:1 situation you are throwing at it, though you may undermine the accuracy of the aperture a touch, and you may have to check focus after stopping down.

(Most enlarger lenses are optimized for 1:2 through 1:10, depending on focal length. They benefit from being reversed, too.)

You need two additional stops for 1:1. At 4:1, you'll need nearly 5 additional stops. Even using a hat as a shutter is no big deal.

Rick "who has reversed a lot of lenses for macro but never by swapping cells in a LF shutter" Denney

[bob carnie]

I am using hot lights, my exposure is 2 seconds f22 at this point.

Bob, the easiest way is with a shorter f.l. lens. If you're using strobes, consider borrowing some of your enlarging lenses.

[erie patsellis]

If you have a packard shutter, that would be ideal, however even without one, you should be able to block light with a black card during lens cap removal and replacement. I've had good luck with my 80mm and 105mm Rodagon at 2-4x (at around f16 to f22)

[bob carnie]

I am using the lens cap for shutter at 2 steamboats with no problem, I am solarizing these negs.
How about the 8x10 lens, I am hoping Jim G or Eddie may see this and suggest a lens, I just not sure which one.
I can get a smaller lens,, I am thinking a 90mm for the 4x5

reversing the lens??? or using an enlarger lens as a taking lens , I am clueless to this.
I am working very fast Rick.... the ability to open the lens wide to focus and compose and then close to working apeture is critical to what I am doing.
My typical shoot is like last Sunday,,,, Load 60 sheets of 4x5 and have the lighting setup and camera ready the night before.... Sunday morning turn on Van Halen and crank through 60 objects.... go to the darkroom turn on Prince and crank through 60 solarizations... and have them dry...

the ability to work fast is really, really important to me.

This may piss off the purist, but I do not care whatsoever about the image taking side of this project , but am more concerned about post film exposure. I have thousands of objects that may or may not work out with the initial solarization. I am totally concentrating on my printmaking skills to get the keepers.
I am using a simple lighting (hot lights from the 40's) dead on positioning of the camera, and wanting as much image size on either the 8x10 or 4x5.
I have a monster skylight that is giving overhead light and my exposures are only changed due to bellows draw which I use the onboard densitometer in my head to calculate.
Plans are to make 40 x 50 silver gelatin lith prints as the end result> the fact that a lot of my objects fall shorter in height than 4 inches is creating my image making problem. I am thankful for any optic help.



Just use a shorter lens. 210 is pretty long for 4x5, and will require about 16" of bellows draw at 1:1. My quick calculation suggests that an 80mm lens will provide the 4:1 you are seeking with the same 16" of bellows draw. The subject will be 4" from the lens, rather than 16" from the lens as with 1:1, so you'll need to make sure the camera does not shade the subject.

Given that most lenses are optimized for 1:10 or more, I would mount the lens backwards in the shutter--rear cell in the front and front cell in the rear--to turn that optimization around. That will get it a lot closer to the 4:1 situation you are throwing at it, though you may undermine the accuracy of the aperture a touch, and you may have to check focus after stopping down.

(Most enlarger lenses are optimized for 1:2 through 1:10, depending on focal length. They benefit from being reversed, too.)

You need two additional stops for 1:1. At 4:1, you'll need nearly 5 additional stops. Even using a hat as a shutter is no big deal.

Rick "who has reversed a lot of lenses for macro but never by swapping cells in a LF shutter" Denney

[bob carnie]

I have disabled the shutter on the 8x10 as it is activated with a bulb and does not work well. I am using the lens cap with absolutely no problems at two steamboats or three depending on bellows.
I have a bunch of enlarging lenses at around 100mm that I do not use, are you suggesting they would work.. I am thinking this won't work as an enlarging lens is a flat field optic design>yes no?? How would one of these lens effect DOField.


If you have a packard shutter, that would be ideal, however even without one, you should be able to block light with a black card during lens cap removal and replacement. I've had good luck with my 80mm and 105mm Rodagon at 2-4x (at around f16 to f22)

[rdenney]

reversing the lens??? or using an enlarger lens as a taking lens , I am clueless to this.
I am working very fast Rick.... the ability to open the lens wide to focus and compose and then close to working apeture is critical to what I am doing.

Just move the front cell to the rear of the shutter, and the rear cell to the front of the shutter. Make sure the lens won't poke in too far to run into something, but I think that will work fine. Same effect as reversing the lens but it keeps the shutter out where you can get to it. It will only affect f-stop accuracy and focus shift if the diaphragm gets moved far with respect to its original position between the cells, but I'd try an experiment with Fujiroid to check it before worrying about it. The lens will definitely perform better reversed at 4:1.

If there was a focus shift, I might try to figure out something else, or just try the lens in standard configuration to see how bad it is.

With the enlarger lens, if it has a filter thread, you can sometimes use the filter thread to make a reversing adapter so that you still have access to the aperture control. Don't forget to shade the lens tightly--the lights are going to be right at the lens and it will flare.

Your two steamboats at 1:1 will become 12-15 steamboats at 4:1, plus any reciprocity effects, unless you increase the lighting. That will slow you down, heh. But it will make a felt-hat shutter a lot easier, too.l

Rick "macro is challenging" Denney

[bob carnie]

Rick

Ok this is starting to make sense. I am checking focus on every shot at wide open so this eliminates the need for a roid.Y/N?
If this works and I can get to the diaphragm and shutter I will be good to go.

I will give try reversing the front and back and report back, the next shoot has over 200 1 inch high cool items. Will take me a couple of sessions.
For solarization, underexposure works to my favour, better black makie lines.

thanks

Bob





Just move the front cell to the rear of the shutter, and the rear cell to the front of the shutter. Make sure the lens won't poke in too far to run into something, but I think that will work fine. Same effect as reversing the lens but it keeps the shutter out where you can get to it. It will only affect f-stop accuracy and focus shift if the diaphragm gets moved far with respect to its original position between the cells, but I'd try an experiment with Fujiroid to check it before worrying about it. The lens will definitely perform better reversed at 4:1.

If there was a focus shift, I might try to figure out something else, or just try the lens in standard configuration to see how bad it is.

With the enlarger lens, if it has a filter thread, you can sometimes use the filter thread to make a reversing adapter so that you still have access to the aperture control. Don't forget to shade the lens tightly--the lights are going to be right at the lens and it will flare.

Your two steamboats at 1:1 will become 12-15 steamboats at 4:1, plus any reciprocity effects, unless you increase the lighting. That will slow you down, heh. But it will make a felt-hat shutter a lot easier, too.l

Rick "macro is challenging" Denney

[erie patsellis]

Another thing I forgot to mention, Componons generally fit into shutters directly as well.

For these types of projects, a few Componons mounted on DB boards and a Sinar shutter are indispensable, but easily done as well with what you have on hand.

I have use enlarging lenses numerous times over the last 30 years, purists/nay sayers be damned...

[bob carnie]

Well I have lots of enlarging Rodagons not being used, sounds like I need to find somone to fix me up.. when it comes to modifications I have 7 thumbs.
Like you , I do not care what the purists say either.

I can see the need for a permanent solution for this magnification issue . Knowing my way of working this will take me a few years to expose all the film I have planned and would like to have a set kit for the Cambo .

I really hope someone jumps in about 8x10 Studio Camera with the Big Barrel lens, Dave Wooten lent me a 8x10 Cambo with a 300 mm lens, I plan to use this camera for a few landscapes and as well use it up north at my daylight studio at the trailer. It would be impossible to take the Studio Camera up there so I need to figure how to do macro with the 8x10, not sure Dave would like me reversing the elements like Rick suggested.


Another thing I forgot to mention, Componons generally fit into shutters directly as well.

For these types of projects, a few Componons mounted on DB boards and a Sinar shutter are indispensable, but easily done as well with what you have on hand.

I have use enlarging lenses numerous times over the last 30 years, purists/nay sayers be damned...

[rdenney]

Rick

Ok this is starting to make sense. I am checking focus on every shot at wide open so this eliminates the need for a roid.Y/N?

Sure. The roid was just for checking to see if there was a problem with reversing the cells in the first place. If no problem, then proceed as usual.

Rick "wondering who else has reversed cells for macro" Denney

[poliweb]

If you can mount your 210 lens on the 8x10 camera, it will cover that format at 1:1 and larger magnifications. The image circle gets bigger as you focus closer. You'd then need less than half the bellows draw that you needed for your 480 lens.

Just an idea

Richard

[bob carnie]

Yes I would have to make a board , but I do know of a group here in Toronto that do these things, very expensive but yes worth the effort.

One thing not stated in my posts, I do not worry about fall off on edges , in fact for the solarization effect this would be a bonus. may actually create a nice effect.


If you can mount your 210 lens on the 8x10 camera, it will cover that format at 1:1 and larger magnifications. The image circle gets bigger as you focus closer. You'd then need less than half the bellows draw that you needed for your 480 lens.

Just an idea

Richard

[rdenney]

I really hope someone jumps in about 8x10 Studio Camera with the Big Barrel lens, Dave Wooten lent me a 8x10 Cambo with a 300 mm lens, I plan to use this camera for a few landscapes and as well use it up north at my daylight studio at the trailer. It would be impossible to take the Studio Camera up there so I need to figure how to do macro with the 8x10, not sure Dave would like me reversing the elements like Rick suggested.

Is the 300 just a standard plasmat?

I just checked shutter threads, and the No. 0 shutter your 90 is in, and the No. 3 shutter the 300 is probably in, both have the same threads front and rear. A No. 1 shutter does not. A plasmat doesn't project down into the lens as much as a Super Angulon, as I recall, and the aperture should be pretty centered between the cells. Shouldn't be a problem at all--the front and rear cells are very similar on a plasmat anyway. If it's a process lens, it's already optimized for 1:1 and won't see any advantage to being reversed.

My calculation is that to use the same bellows draw on the 8x10 camera as you have used to get 1:1 with a 48cm lens (which is 38 inches or so), you need a 190mm lens to get 4:1. The 210 would need a bit more, but not that much. So, use that lens. Coverage is not an issue--you'll have enough.

But the 210 is probably in a No. 1 shutter, so you can't reverse the lens cells on that one--the threads are a different size. Try it as it is.

If you try to do it using the Cambo 8x10 camera, you may not have 38" of bellows draw. For that one, you may need to use a shorter lens. Even the 90 will work--you'd need 450mm of bellows draw. The image circle at 4:1 is about five times what it is at infinity--coverage won't be a problem (even a 90mm lens for 35mm might be enough to cover 8x10 at 4:1).

Rodagons for enlarging small format are optimized for 1:10, and for large format are 1:2, based on reading I did last week. The shorter ones will benefit from reversal more than the longer ones, and the longer ones may be fine just as they are.

Rick "suggesting two tripods, if not an optical bench setup" Denney

[bob carnie]

Rick

It is a fujinon . w 1:5.6/300 Copal shutter.

[rdenney]

Rick

It is a fujinon . w 1:5.6/300 Copal shutter.

Yup, standard plasmat in a No. 3 shutter. Should be no problem reversing those cells, but I'll bet you'll need a shorter lens if you want to do 4:1 magnification.

Rick "not thinking an 8x10 Cambo has that much bellows draw" Denney

[bob carnie]

Thank you all for your help, my brain hurts now, before today all I new was I was using a 210 for the 4x5 and a big boy for the 8x10.

I will consider all advice and modify my existing gear, and give the small objects a go and post some results in a couple of weeks.

[Bill Burk]

Could you use an enlarger? Maybe just put the film on an easel and the object to be photographed in a negative carrier.

Ok not literally, but to keep your head from hurting it might be easier to imagine the entire setup this way.

[bob carnie]

Now you are talking my language.

Could you use an enlarger? Maybe just put the film on an easel and the object to be photographed in a negative carrier.

Ok not literally, but to keep your head from hurting it might be easier to imagine the entire setup this way.

[Jim Jones]

Yup, standard plasmat in a No. 3 shutter. Should be no problem reversing those cells, but I'll bet you'll need a shorter lens if you want to do 4:1 magnification.

Rick "not thinking an 8x10 Cambo has that much bellows draw" Denney

According to S. K. Grimes http://www.skgrimes.com/products/new-copal-shutters/standardcopals the Copal #3 thickness is 32mm and the front to iris dimension is 17.7mm. Other Copals have similar differences between front and back. Thus, the iris is not centered between the cells. This may be a problem in reversing the cells. I tried reversing a 90mm Optar in a Wollansak shutter with dismal results.

An old Leitz 21mm Angulon reversed on a 4x5 gave about 4X magnification. With three dimensional subjects the DOF is quite small, even with the lens stopped down to an indicated f/22 (working aperture about f/90). At that aperture, diffraction raises its ugly head. This might not be as distracting in Solarizated images as in straight photography.

Most enlarging lenses work well when reversed for greater than unity magnification. Mounting by screw-in or Kodak series filter rings epoxied into lens boards is easy. To keep people from stopping down more than a few stops less than optimum aperture, most enlarging lenses can't be stopped down very far. They are even worse than camera lenses when seeking maximum DOF. Edward Weston had to have the aperture on an inexpensive Rapid Rectilinear modified for an aperture of f/256 (according to some sources) for some of his macro photography. Hmm. Maybe a junk box RR is the answer!

[rdenney]

I just tried it with a 90mm f/5.6 Super Angulon, which is, of course, in a No. 0 shutter. It doesn't work--the front cell in the rear threads screw in too far and interfere with the aperture. A quick look at a Grandagon layout suggests it will have the same problem. But it should work with plasmats and double-gauss lenses, except that the most useful of those will fit in a No. 1 shutter that does not have the same threads front and rear. So, you're probably right in enough cases that I should just withdraw the suggestion.

The Rodenstock enlarging lenses specifically can be reversed, but most of them have an optimal range down to 1:2 and might be fine without reversal. If I could not reverse a standard lens, I would switch to using an enlarging lens. At 4:1, exposures are going to be long enough not to need a shutter.

But 4:1 will also reveal a range of sub-optimalities not visible at 1:1.

Rick "noting that 4:1 is four times as challenging as 1:1" Denney