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RPMDesign
09-06-2006, 01:53 PM
Here's my first camera and photo from it. 35mm film, .23mm pinhole, 38mm focal length. My goal was to make it as compact as possible! Rick

Attached files http://f295.f295.org/uploads/1_6785.jpg (http://f295.f295.org/uploads/1_6785.jpg)

RPMDesign
09-06-2006, 01:57 PM
Here's an inside view.

Attached files http://f295.f295.org/uploads/2_597.jpg (http://f295.f295.org/uploads/2_597.jpg)

RPMDesign
09-06-2006, 01:58 PM
and a photo from my first roll.

Attached files http://f295.f295.org/uploads/3_3091.jpg (http://f295.f295.org/uploads/3_3091.jpg)

SteveH
09-06-2006, 06:05 PM
Very cool, congrats !
What are the specs on your camera ??

RPMDesign
09-06-2006, 07:09 PM
f168, 38mm focal length, .23mm pinhole. But I made the hole by just pushing a pin through some black foil. I guess I should try one of the methods mentioned in this forum...

moot
09-08-2006, 04:12 PM
Impressive camera, and an interesting image with a lot going on. Looks like a great success!

murrayatuptowngallery
09-08-2006, 08:08 PM
Deco Cool

Andrew
09-08-2006, 09:52 PM
I'm most impressed... I should spend more time over this side

Marv
09-08-2006, 10:29 PM
Very nice design, great image potential with the format.

That's an interesting image, lot's of repetitions.

RPMDesign
09-08-2006, 10:38 PM
Thanks everyone. I'm learning that the downside to a curvy shape is that it's hard to hold it still up against anything... So I have to put it down on something flat.

I also had trouble telling if the film advanced, so I had to add a paperclip to the advancer so that it wouldn't spring backwards. The clip helps keep the tension in the film.

Hopefully more tests and photos this week.

jvh
09-13-2006, 06:18 AM
Looking forward to more pictures from this very interesting camera.

RPMDesign
09-18-2006, 03:00 PM
I posted some images from my second roll here:
http://f295.f295.org/uploads/Blah.pl?m-1158601411/s-0

My thoughts on the camera:
I'm very happy with the shutter and the way that it is integrated into the lid.
I really need to re-do the pinhole - These pics were from a .26 hole made by just sticking a pin through some black foil - so many images show the burrs on the edges. I just bought some of the Gilder grids to replace this one out.
I overestimated the space needed for the film canisters - does anyone have exact dimensions of a standard 35mm film roll? I measured it at 1" diameter, but it's definitely smaller, and between that and my leaving an additional 1/16" space, it's pretty loose. I also left 1/16" space between the body and the lid, and this is WAY too much. Next time I'm thinking of working only in metrics, and leaving no more than a half a millimeter all around so that the lid fits really snugly. Since the sides are made of cardstock, there's plenty of give anyway for it to fit on.
I'm thinking of integrating a tripod mount into the bottom.
The curvy back makes it hard to hold up against a surface, but I like the way that it looks so I think that I'm going to keep it in the revisions.
I do need to integrate a tensioning device into the winding side of the advancers. I added this in after roll #1 and it worked very well, but it looks a bit jerry-rigged in the existing camera.
I also completely glued together the center of the camera, and so I can't access the pinhole without cutting the box apart - which I'll do when I replace the pinhole, but in the next version I won't do this.
Am I correct to think that the proper curve of the film should be the radius from the pinhole to the camera?
Any thoughts and suggestions very welcome!

poptart
09-18-2006, 03:35 PM
Cool camera. The "proper" curve is radiused from the pinhole.

biggoodwolf
09-18-2006, 05:44 PM
This is a wonderful camera and format, and those stairs are very original, like something out of Bladerunner

moot
09-19-2006, 01:05 AM
I overestimated the space needed for the film canisters - does anyone have exact dimensions of a standard 35mm film roll? I measured it at 1" diameter, but it's definitely smaller, and between that and my leaving an additional 1/16" space, it's pretty loose. I also left 1/16" space between the body and the lid, and this is WAY too much. Next time I'm thinking of working only in metrics, and leaving no more than a half a millimeter all around so that the lid fits really snugly. Since the sides are made of cardstock, there's plenty of give anyway for it to fit on.


There is probably an ANSI or ISO standard for the cannisters, but I've not seen it. I just checked a roll of Kodak color neg film and a roll of Fuji. The diameter of the cap is 0.990" +/- 0.005". The Kodak was a couple of thousandths less than 990 and the Fuji a couple over. The heights (outside surface of the caps, not the spool) is 1.680". The Kodak and Fuji were within 0.002" being equal. I suspect the cans are the same, and the slight difference is dependent on assembly forces.

A half-millimeter (0.020") all they way around will be fairly loose, but if you don't have a way of making accurate holes it's probably safer to be a little generous. 1/16th (0.063", 1.6mm) is very generous, however. You could also put a bit of tape on the film cannister to take up some of the slop. Or use some thin adhesive-backed foam in the camera.

RPMDesign
09-19-2006, 01:17 PM
Thanks moot, poptart and biggoodwolf,

moot,

Two questions for you - how did you measure? I had just used a ruler, but calipers or a micrometer would obviously be more accurate, and it sounds like that's what you did.

Also, if you did use a micrometer, would you mind also measuring the spindle diameter for me? The light tightness depends on the spindle going tightly through the lid of the camera, and on this one my hole was slightly small and I needed to Dremel it out some to get the fit.

I do have an accurate way to cut the pieces - I was using a cheap laser cutting company to cut out my pieces in cardboard (have you ever tried to hand-cut a circle? Ugh.).

I did fill up some of the space inside, but the perfectionist in me... And, I plan on making a revised version anyway.

moot
09-19-2006, 01:42 PM
I used dial calipers. Spindle diameter is 0.435", top and bottom are the same. A 7/16" (0.4375") hole might work OK. If it ends up a bit tight a light touch with a round file should open it enough.

I admit that appeals to me, using a laser cutter to make the parts for a homemade cardboard camera.

moot
09-19-2006, 08:56 PM
Wow! I don't think you'd do quite that well with an X-Acto knife.

Do I see another DIY pinhole camera kit in the making?

RPMDesign
09-20-2006, 01:18 PM
Yeah, and this black letramax is really HARD. It breaks X-Acto tips left and right. But it's really matte and nearly black which is great.

My plan is to first redo this camera with all of the problems that I've found fixed. And then maybe variations on a theme, like a 25mm and 50mm focal length, but the same basic design. Or a square format. I had it in my mind to come up with a way to swap out the fronts on a single body so that I could change the focal length on one camera, but I haven't quite figured out how to do it yet. I might try to mock something up with the spare pieces that I have from this camera and see if a solution reveals itself. Next week (hopefully), new photos with this camera using a much smaller (.15mm) Gilder grid aperture.