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Mkillmer
30-Mar-2014, 18:26
I've just built an LF camera out of bits and pieces:
https://farm8.staticflickr.com/7387/13510843864_beb68fba85_z_d.jpg
The lens is an ancient 13 1/2" Cooke Aviar Anastigmat.
Unfortunately the bellows draw prevents me from doing "Head and Shoulders" portraits.
Is there an solution to modify the optical path with something like a close-up lens to allow name to use it up close?
The lens has a diameter of 10cm.

Mark

vinny
30-Mar-2014, 18:35
Yes, a close up filter or a shorter lens are your 2 options. An extension lensboard works on some cameras but doesn't look like it will work with yours.

Mkillmer
30-Mar-2014, 18:56
Any ideas on how to get a 10cm closeup lens? He rear lens is a few cm smaller, can I put the lens on that side?

Francisco J. Fernández
30-Mar-2014, 21:01
Hi, I sometimes use these accessories to increase the length of bellows (or reduce the focus distance, which is the same or almost the same).

But other times I used close up lenses, when I could not pay much. Or when you could not do anything with a bellows (zoom in on a Fuji 617, I do it with close up lenses).

I hope this is helpful.








http://www.ebay.es/itm/Focusing-Ring-Helicoid-For-DIY-4x5-8x10-Large-Format-Camera-Or-Lens-Modification-/271430116759?pt=US_Lens_Adapters_Mounts_Tubes&hash=item3f327ee597&_uhb=1


http://www.ebay.es/itm/New-Extension-Lens-Board-For-Linhof-Wista-Shen-Hao-4x5-Large-Format-Camera-/271186737287?pt=US_Lens_Boards&hash=item3f23fd3887&_uhb=1



http://www.ebay.es/itm/22mm-Extension-Lens-Board-Horseman-80x80mm-45FA-HD-VH-R-4x5-Large-Format-Camera-/271340527433?pt=US_Lens_Boards&hash=item3f2d27df49&_uhb=1


http://www.ebay.es/itm/30-40-70mm-Extension-Lens-Board-Tube-Ring-Horseman-80x80mm-45FA-4x5-Large-Format-/271345399171?pt=US_Lens_Boards&hash=item3f2d723583&_uhb=1

Regular Rod
31-Mar-2014, 00:54
That box section behind the rear upright with the back on it needs to be deeper. Build a deeper box for the back. Like you have now but deeper. Make a mock-up out of card to determine the depth necessary.

RR

Mkillmer
31-Mar-2014, 02:57
That box section behind the rear upright with the back on it needs to be deeper. Build a deeper box for the back. Like you have now but deeper. Make a mock-up out of card to determine the depth necessary.

RR
Great suggestion - I think you are spot on. I set up an 8x10 with a 14" lens next to the Aviar, and discovered that I only need 3 cm extra to get "Heads and Shoulders".
I will build a 4 cm extension to the red box and should be set. That'll be next weekends project!

ic-racer
31-Mar-2014, 04:03
Close up lens just shorten your lens focal length. Why not just get a shorter focal length lens in a shutter. You will need a lot of bellows draw to focus that lens. For example a camera made out of an 8x10 enlarger, rather than what looks like the focus assembly for a medium format enlarger.

What is your film format size? How much bellows draw do you have now? You can figure out how strong of a diopter you need or how much more bellows draw you need with the thin lens equation

1/p + 1/q = 1/f

You can convert you 13" lens to diopters (338mm = 3 diopters, etc) so a 1+ diopter lens makes your existing lens into a 250mm lens etc.

Mkillmer
31-Mar-2014, 04:47
Thanks for the input ic-racer.
I'm trying to use up the bits and pieces that I have laying around (mainly this beast of a lens!).
I tried a small 49mm +1 closeup lens mounted in cardboard infront of the lens.
close focus went from 2.5m away from the subject to <1m away- that was too close.
would a larger size closeup lens make a difference?

ic-racer
31-Mar-2014, 15:07
Thanks for the input ic-racer.
I'm trying to use up the bits and pieces that I have laying around (mainly this beast of a lens!).
I tried a small 49mm +1 closeup lens mounted in cardboard infront of the lens.
close focus went from 2.5m away from the subject to <1m away- that was too close.
would a larger size closeup lens make a difference?

The "+1" lens was too close, even with the bellows collapsed all the way?

ic-racer
31-Mar-2014, 15:13
As a visual reference, here is an example of my 4x5 camera that can focus a 300mm lens for a close portrait.
113082

Regular Rod
31-Mar-2014, 17:10
great suggestion - i think you are spot on. I set up an 8x10 with a 14" lens next to the aviar, and discovered that i only need 3 cm extra to get "heads and shoulders".
I will build a 4 cm extension to the red box and should be set. That'll be next weekends project!

:)
rr

Mkillmer
31-Mar-2014, 19:17
As a visual reference, here is an example of my 4x5 camera that can focus a 300mm lens for a close portrait.
113082

It's huge! :p
But my experiment with a +1 diopter brought the camera to 1m away. Would using a full sized diopter make a difference? The one I used was only 49mm, but the lens is about 86mm wide. It seems I want a +0.5 diopter, but they don't seem to exist - especially in this size...

ic-racer
31-Mar-2014, 20:10
But my experiment with a +1 diopter brought the camera to 1m away.



Lenses don't move cameras, only people move cameras :) Why did you move that close? To achieve focus, or to frame the subject the way you wanted it?


Would using a full sized diopter make a difference?

Probably not if you stop down. You are only using that full lens diameter when focusing or shooting wide open.

Mkillmer
31-Mar-2014, 20:55
Lenses don't move cameras, only people move cameras :) Why did you move that close? To achieve focus, or to frame the subject the way you wanted it?
.

1 meter was the maximum(!) distance for focus.

AtlantaTerry
31-Mar-2014, 22:49
Mark,

Am I right in thinking you made the camera out of an old enlarger?

What about having a machine shop make (in essence) an extension tube?
One end would have threads that screwed into the camera's lens board.
The opposite end would have threads that accepted your lens.

Kinda sorta like some of the items in this FS thread:
http://www.largeformatphotography.info/forum/showthread.php?112106-FS-80mm-horseman-lens-boards-and-top-hat-set

While you are looking at the ground glass have someone hold the lens in their hands and move it away from the lens board. (Free lensing.) Then note how long the tube should be. Maybe add a couple mm just to be sure.

Would that not work?

ic-racer
1-Apr-2014, 07:04
1 meter was the maximum(!) distance for focus.

With the bellows collapsed all the way? In that case the rear assembly is too long.

ic-racer
1-Apr-2014, 07:06
Great suggestion - I think you are spot on. I set up an 8x10 with a 14" lens next to the Aviar, and discovered that I only need 3 cm extra to get "Heads and Shoulders".
I will build a 4 cm extension to the red box and should be set. That'll be next weekends project!

You built that but you have an 8x10 camera? Why not mount the lens on the 8x10 camera?

Mkillmer
2-Apr-2014, 18:50
You built that but you have an 8x10 camera? Why not mount the lens on the 8x10 camera?

The lens weighs 4kg. I'm certain something would break. Besides - more cameras is better... Isn't it?

ic-racer
2-Apr-2014, 19:21
The picture is deceiving; it does not look that heavy!