Show off your Large Format camera!

[Barry Kirsten]

This is certainly LF, but pinhole. When I got a box of 5x12 x-ray film from a forum member in exchange for some bits and pieces I immediately saw a use for it. The resulting camera took months of trial and error to get to this stage, and it still needs work.



The film plane curve has a 5" (127mm) radius and I intended the film-pinhole distance to be the same but it ended up 135mm. The 0.5mm pinhole is on a movable plate to allow rise and fall of +/- 15mm to prevent curved horizon lines if the camera were pointed up or down. The good news is that the box is light-tight. But my big surprise on developing the test sheet was that the pinhole is too close: I see an image circle which I have never seen before on a pinhole camera.



The IC measures 270mm and drawing it all out on paper shows me that for the 128 degrees of coverage, I have to move the pinhole away from the film another 6mm to cover the full 12" of film. Hence the work that still needs to be done.

This was my first ever experience of x-ray film. Prior to testing the camera I cut a sheet of the film into 4x5s to test film speed and development. I found that a good speed was asa 100, and developing time of 8 min. in PMK Pyro is just right. I was pleasantly surprised with the results of the film, Kodak dental panorama film 198 7627. It's double-sided and oh, does it scratch. I don't have large enough trays for film of this size and used the cat litter trays I use for paper, which unfortunately have a small protruding dimple in the base - a no-no. No mor 5x12 negs until I get some proper trays. All in all I'm very satisfied with this project so far. The neg was over exposed so I need to re-evaluate exposure based on an aperture of f/270, and perhaps even change to a 0.4mm pinhole in order to improve sharpness. Here is a cropped image, lightly worked in LR.

[NedL]

Hi Barry!

Nice job on that camera. I think the "image circle" you are seeing is actually the pinhole being obstructed, try looking at the mount for the pinhole itself and seeing if there is a way to make it flatter or make the pinhole a little less recessed. I've got a curved plane camera that is similar ( 6x11 up to 8x11 paper, 5.5 inch curved plane radius, 5 inch "focal length" ) and it is very wide angle -- you need to make the pinhole mount very flat!

Well done!
Ned

[Barry Kirsten]

Thanks Ned, and good to hear from you again. I'll look into that. I was always a bit concerned with the mounting plate which was 2mm aluminum, all I had; I would have used 1mm thickness if I'd had it. I've found mounting those EMS apertures very tricky and in this case stuck it onto a small brass washer and the lot recessed into a hole in the aluminum plate. I know a lot of people use photo tape to mount the pinhole but I don't have a fine punch to make the right size hole. I can see I'll have to look at pinhole mounting more closely. Thanks for your helpful comments.

[NedL]

I want to try a 0.1 or even a 0.05 mm EMS aperture on a macro pinhole camera, if Earl has any that small. Been meaning to write him about it. I'm thinking of making an 8x10 or 11x14 camera to make pinhole photos of the faces of ants, bees and beetles BTW I've run into that same "vignetting" problem on a lot of my curved plane pinhole cameras, and often end up fussing with the mount to remove obstructions... it's a small angle to the edges of your film or paper. Have fun!

[Nathan Smith]

[QUOTE=Westerman;1371552]Here is my newest camera acquisition. I think it's a homemade 8x10 camera. I may need to improve the mount for the front standard to be more stable and give me more movements. I have a FKD tripod on the way from Russia that should give me a more stable tripod. I've been taking photos with x-ray film and am still trying to find the best way of developing them.

This is a very interesting camera - what format is it, 8x10? Do you have scans of any of the shots with it?

[JamesCookPhoto]

Finally my Intrepid 4x5 arrived. 12 weeks after ordering. Can't wait to get some film into the holders.
I've got a Fujinon 150mm f/5.6 as my first lens. Should be a good place to start.

[axs810]

My new to me Calumet C1 8x10 with Kodak Commercial Ektar 14" lens. I still need to test the film holders I bought and finish getting the rust off this tripod. It's weird even when I get the rust off with apple cider vinegar, rinse it, then coat it with silicon spray a few days later the rust appears in areas I'm unable to get to. Going to keep working on it though I love this tripod for this camera set up.


PS- After taking this photo I realized the tripod is not level and one of the feet are backwards. Glad I made this mistake when taking a goofy photo rather than on an actual shoot lol. I would have re-shot this but this was just a goofy photo taken before going out to dinner.

[blindpig]

Good looking camera Barry.Looking forward to seeing more pictures from it as you shake it out.The only down side to camera making(for me anyway)is it can become more fun than shooting pictures.Keep up the good work.
Don

[Luis-F-S]

My Deardorff along with Fuji 210 L & 12 inch commercial ektar
The lensboards are 4 1/2 inches in size (not the usual 4 inch)

The 4x5 back is later vintage and has a little play when attached.

Attachment 160194Attachment 160192Attachment 160193

Best,

Serge

If the pins are filed you can rotate them to take up slack or you can replace them. You can also use black masking tape on the inside of the back. I usually use black masking tape to tighten lens boards.

[andrewch59]

Great lens Serge I have the 8.5 inch