oatmeal pinhole failures, help!
I am a teacher and have made the oatmeal containers pinhole cameras and am struggling very much with the results. The images are turning black consistently. I think I am doing everything to the book but to no avail. Any suggestions before my next class tomorrow.
Well, black is total exposure of the paper; is there any chance the paper has been accidently exposed to daylight at any point in the process?
Can you briefly go over how you do this process?
Hi Anna--welcome to APUG. There's no need to make the same post in three different threads. They'll all come up in everyone's "New Posts" view, and the discussion will be more coherent if it all takes place in the same thread.
I suspect, as the above poster suggests, that you've exposed the paper to daylight. Did you load the paper into the oatmeal boxes in the dark or under a safelight?
1 cut a 1"x1" square, 1/3 up from botton of container
2 cut a 1.5"x1.5" square of tin from a pie tin.
3 tape tin to oatmeal container with electrical tape
4 w/ no. 10 needle, drill as little as a whole as i possibly can, ( this i think is the problem, hole to big, need smaller needle.)
5 use electrical tape for shutter.
6 spray paint lid with flat black spray paint
in darkroom place unexposed paper in container, close lid. expose for 2 seconds or less.
oh, sorry about the multiple posts. this is my first time in a chat room.
yes, unexposed paper, under a safe light in the darkroom. i feel so silly because i have done this every year and it has not worked this year or last.
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It is possible that the hole is too big.
How about the development procedure? What chemicals are you using, what dilutions, time and temperature (and of course this should take place in the dark or under safelight as well). What type of paper?
we are using a generic of paper and chemicals, called arist. dilutions of the chemicals works fine for all the other prints done with enlargers. i don't think that is the problem i think perhaps it is the hole. i think i just need a smaller needle, i didn't think they could get smaller.
i don't know what the etiquette is but i am leaving for the day and will be back in the morning, thanks for your help and suggestions.
Use several layers of opaque tape on both sides of the lid and make sure to leave some room inside so the top will fit snuggly. Paint alone doesn't work very well. I'd also suggest getting a roll of duct tape and encircling the camera and base with a couple layers, then putting the pinhole shim and shutter in place. It would also be a good idea to spray the inside of the camera flat black.
This was the procedure we did a couple years ago in a pinhole workshop taught by Dan McCormick using oatmeal cartons. Even having done all this we ended up with a few cameras that had light artifacts caused by the reflection of the image light off the film and onto another area.
I suggest using quart or gallon paint cans as an alternative to the oatmeal box. New cans can be purchased at a paint store or home improvement store very inexpensively, and they hold up longer than cardboard. Again, paint the inside and lid flat black and carefully drill or punch a larger hole in the side over which the pinhole shim is placed. Be sure to have the can secured well (in a vise or clamped to the table) if you try to drill the hole and preferably use a drill press for that operation. You don't want to freehand the cylindrical can which can slip and end up with the drill bit going where you don't want it, like your hand. A hand file will also be needed to remove the burr around the hole.
Paint or hardware stores will also usually give you those nifty little paint can keys gratis.
I'm not sure if you can get a hole too big with a needle and a two second exposure for paper. Paper isn't very sensitive, so even with a sizeable hole I doubt it would be completely black. I would bet on a light leak. You might want to stick a piece of that paper into the chemicals before you leave the darkroom to make sure that package did not get damaged (exposed). An oatmeal can must have an FL of about 75 to 100 mm directly opposite the hole, and that would put it in the .4 to .5 mm range for the hole. If you really think the hole is the problem, expose the paper for a much shorter time (half a second), and see what you get. Several of the guys at f295 flash their paper first to get the speed up into the many seconds range instead of the many minutes range.
One thing that might help to determine the proper pinhole size would be Pinhole Designer:
Also there is a pinhole specialist forum at http://www.f295.org for even more pinhole stuff.