A simple 11x14 roll film camera

I'm building a 4x5 view camera now, but when finished I'm thinking about building another 11x14 roll film camera again. This is due to the evil influence of green xray film. :)

A few years ago (25) I experimented with a very simple 11x14 camera that I could use with roll film. One main problem for building really big cameras is the film holders. They can cost more and weigh more than the camera itself.

In high school, I had a K-20 arial camera that used 5 1/2-inch-wide roll film, I think tri-x. It was a military surplus 4x5 camera with a good lens focused at infinity. I took one of my favorite photos in my life on a beach one day with that camera.

I built a box out of plywood that was shaped like a very thick piece of pie. It had a circular film plane because I used a single element +3 closeup lens as the camera lens. These are positive meniscus lenses with a focal length of ten inches. The lens center, where is placed a single F80 aperture plant (a 1/8-inch hole drilled in a sheet of aluminum), is located about an inch and a half in front of the concave surface. The camera was 12 inches tall, 18 inches wide and 10 inches deep and weighed about 5 lbs. Looks like a small suitcase.

Simple lenses have spherical aberration and a spherical focal plane. There were many cheap old cameras that worked that way. My camera back was made of thin tempered masonite, which was able to take that curve. I set the curvature to be good compromise between the larger radius at the middle (about 11 inches) and the smaller radius that would be on a sphere with 11-inch radius where the upper and lower edges of the film would rest. I set it for the hyperfocal distance for this lens using blur disk of 1/50 of an inch, larger than most would use. This would give sharp focus from 2 meters to infinity.

Optically, it worked really well, and I still have a few of the test negatives I shot on 11x14 vcrc enlarging paper. I had ortho litho film also 11x14 that I planned to use with it. These sheets, I taped together using electrical tape, and would wind on reels of PVC pipe. I viewed the tape through a small red window to align them with the camera.

It worked really well with vcrc paper, but the ortho litho film reciprocity failure prevented me from using it. Optical big success, but mechanically an almost but not quite, got back shelved and forgotten. I called it my almost a pinhole camera, although it was much much sharper than any pinhole.

Now I'm playing with green xray film. Hmmmmm. That could work there. I could use some kind of black plastic roll stock, or maybe aluminum coil stock 12 inches wide and tape xray film to one side. Put marks and numbers on the back to find position. Hmmmm I think it would work after mechanical bugs out. I have some black posterboard from Walmart that may work, too.

I threw the prototype away when I moved from that home. It was all rat chewed anyway, and kinda klunky too. This project wouldn't be all that difficult. The shutter speeds would be a second or so and longer, so lens cap works. Have reciprocity chart for xray. In the thinking about it phase now...

I used an open frame wire view finder on a repeatable tripod mount, so that I placed the viewfinder on the tripod, and decided on the direction, then removed the finder and installed the camera also with repeatable mount and took the photo. This eliminated parallax and was very quick and positive. Imagine that 11x14 wire frame curved on about a 9-inch radius viewfinder. Really big and easy to use. An almost blind person could use this camera.

Comments and suggestions encouraged.

X-Ray film is not evil

I am still working on 14X36" box camera

I will post progress in ULF

I recently bought some 0.1mm stainless sheet on roll. It is quite flexible and was delivered rolled up about 10cm diameter. But very shiny of course.

Curious about your build.

Why not get some surplus 9.5" Aerial rollfilm ? It's a little smaller than 11" but it's already on a roll.

Tracy, thanks for the response.

I would think about that if I had a supply. Where is that available today? I could also use smaller xray film like 8x10 with a more regular lens I already have, too. hmmmm. thinkingggggg.

One problem with that cylinder film shape is the pictures need to be taken pretty much with the camera level, otherwise there is some weird looking distortion. I forgot about that.

Havoc,

Thanks for the response. That is really thin. Paint probably wouldn't stick very well (needs flat black) and thicker to not fail from repeated tapings and untapings. Probably expensive. Coil aluminum stock at home depot very cheap for flashing roofs. What are you using that for? Shim stock?

Tin Can,

Yes, green xray film is very evil. It calls to you to repeat past failures again! Kidding of course. Whenever you do something new to you, learning happens. I'm 71 years old and have time for a limited number of repeated failures. :) How will you push those 36-inch-long sheet film holder slides in without bending them? I built a film holder once that opened l like two barn doors once. It had light leaks, too though. At one time, I thought barn doors would be easier to seal than sliding film holders.

I am 73 and going blind, I no longer drive

Huge cameras are best for me

i use DIGI as vision aid

I prefer fun

not art

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Originally Posted by Alan Townsend

Tin Can,

Yes, green xray film is very evil. It calls to you to repeat past failures again! Kidding of course. Whenever you do something new to you, learning happens. I'm 71 years old and have time for a limited number of repeated failures. :) How will you push those 36-inch-long sheet film holder slides in without bending them? I built a film holder once that opened l like two barn doors once. It had light leaks, too though. At one time, I thought barn doors would be easier to seal than sliding film holders.

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