migrated article: “Pintoid” Camera /Film Processor
“Pintoid” Camera /Film Processor
by Jonathan King
Altoid tin pinhole cameras
Altoid pinhole cameras, or “Pintoids”, have been covered on the internet on
web sites (see links) and in discussion groups. When I saw this described, I was intrigued – I’ve made a couple of pinhole cameras in the past, and found that the inexactness of the camera just lets the fun and joy of image making to dominate.
A Pintoid by itself is a fun project, but it seemed that the next step would be to turn the camera into a self contained processor as well!
Processing the film in the camera eliminates most of the film handling, makes daylight processing easy, and has the advantage of keeping the procedure simple for someone who is not familiar with black and white processing. I’ve built pinhole cameras with a group of 10 year old kids. It worked and they were excited, but I didn’t feel it gave them as good an introduction to the ‘magic’ of black and white photography as it could have.
Most Pintoid users have used 35mm film, but I really didn’t like the idea of
cutting, handling, and processing small strips of film. I noticed that the Altoid tin is just about the size of 2 ¼ x 3 ¼ sheet film. J&C Photography stocks Efke 100 film. It turns out that the 2 ¼ x 3 ¼ film fits the Altoid tin quite well. In fact, the film corners catch the tin corners such that there is a spring force that holds the film in place without tape! With normal handling, I haven’t had any film shifting.
There is actually a good deal of preliminary work before camera construction can begin. Most of my Pintoids are Licorice
Start by drilling a hole about 1/8” (about 3mm) in diameter just under the cross bar of the “T” in “ALTOIDS”. The exact diameter is not important. A coat of primer then flat black paint on the inside will reduce reflections and protects the tin from the processing chemicals if you make the processor version (Yes, they do attack the tin). I used spray paint from the local hardware store.
I have a pinhole that I bought (Lenox laser), but I usually make them. I mount the pinhole in the tin with black bookbinding tape that I got for repairing some film holders. Any strong tape should work just as well. I make a shutter from a combination of the bookbinder tape and black electrical tape. Cover the hinges with tape to prevent light leakage. I used the same book binder tape, but anything opaque and sticky should work.
There are many ways to make pinholes, but I’ve found this one easy and quick. I’ve used aluminum cans and brass shim material. If you use aluminum cans, make sure to sand off the paint exterior and the plastic coating on the inside.
I’ve make pinholes with pins and tiny drill bits, pushing or drilling through the metal, but I get better results, especially for smaller pinholes, by just dimpling the metal with a pin, then sanding the dimple open. I start with 600 grit sandpaper and progress to 1500 grit, the finest I can get at locally.
I check the pinhole diameter and roundness with my scanner by scanning at the maximum resolution and checking for burrs or other imperfections.
I normally make several pinholes at once on a single piece of metal and then cut out the ones I want to use. It is easy to adjust your technique to make larger or smaller pinholes, depending on what you are looking for.
The Pintoid processor is a modification of the Pintoid that will let you process the film in the camera without a darkroom! After a bit of searching, I found inserts for compression fittings in the plumbing area of the hardware store. They are a short copper pipe with a flange on one end. I use a ¼ inch fitting.
I found a location of the side of the tin that was as high as possible without interfering with the lid. For the fitting I used, a ¼” diameter hole let the pipe through, but not the flange. I then soldered the insert to the tin. A soldering iron used for electronics worked, but took a minute or two for a well wetted joint. I didn’t have enough finesse to use a plumbing torch – I just charred the Altoids tin
For a hose, I use a thin ¼” O.D. tubing. The second best tubing I found was heat shrink tubing, shrunk and clamped to minimize any chemical leakage. A large paper clip clamped the free end of the tubing, preventing light and chemical leakage, and the camera/processor is done!
While it is possible to pour and drain developer, stop bath and fixer through
the tubing, a monobath developer would be much more convenient.
Monobath developing is a technique sometimes used in the past for press
photography to minimize processing time was a quick development in a
monobath – a combined developer and fixer. Given enough time, the fixer will remove all silver salts, exposed and unexposed. The trick is to have the developer convert the latent image to metallic silver before the fixer goes too far in removing the silver salts.
Most formulas are several decades old from when this technique was in wider use, but a modern formula (from Donald Qualls, via www.photo.net) is made with currently available photo and household chemicals.
Qualls Monobath formula
Kodak HC110 film developer
concentrate (U.S. version) 16ml
Ilford Rapid fix 10ml
Household Ammonia 50ml
Water to 250ml
Process for 7-10 minutes at 68F. Agitate continuously for the first minute, then 10 seconds each 30 seconds. This is more agitation than is normally used, but it is important to quickly develop the image before the fixer removes it.
After processing, open the camera and wash the film. The antihalation backing might not be totally removed. Extra fixing or washing in a solution of 1t sodium carbonate (washing soda) or just water may complete clearing the backing. Use whichever works best for you.
The volume of the Altoid tin is about 90ml. If filled, the hinge will leak, so a
practical maximum volume is about 40ml. I’ve successfully used volumes
between 25ml and 40ml.
Film speed can be a stop or two less in a monobath developer, so I started
rating the Efke 100 film at E.I. 25. The pinholes I use have an f-stop of about f/64 so exposure times quickly got into reciprocity failure, requiring even longer exposures. Full sun exposures were about 1 second, while indoor scenes or were 15 minutes to an hour.
I added a few construction photos, and a quick image, just to prove it works . Of course, being December, daylight hours are short and work-filled, and the weekends have been gray, so my office is what you get!
Links: Marcy Merrill’s Pintoid site: http://www.merrillphoto.com/pintoids.htm
Pinhole Designer program (free!, Windows only): http://www.pinhole.cz
Pinhole Calculation site: http://www.mrpinhole.com
comments from previous article system:
By Donald Qualls - 01:34 PM, 01-28-2005 Rating: None
Interesting. I've tossed a bunch of Altoids tins because it seemed the hinge leak would require sealing the entire lid with tape every time I loaded them -- but the ability to use 2x3 format film is one I'd missed. Given relative prices and exposure times, I'd be strongly tempted to use the J and C 200 film (though that might require installing a sliding shutter to make exposures shorter than one second practical with a relatively fast pinhole like this one).
What's your source for the Hastings Monobath? I ask, because it's almost identical to one I created a few months ago (originally posted to photo.net Black and White Film and Developing forum and listed on the Massive Dev Chart at digitaltruth.com) -- I used 10 ml more ammonia and processed at 75 F for six minutes with Tri-X and normal agitation (full first minute, then ten seconds per minute); I found the film lost shadow detail, but had normal seeming midtones and highlights, as if it were 1-2 stops slower and pushed back to EI 400. Different films typically require slight changes to monobath formulation, also; different reaction rates in developer and fixer require tweaking the ratios to balance the two processes.
By jking - 10:01 PM, 01-28-2005 Rating: None
My apologies to Mr. Qualls. In my notes when I was researching monobaths, I mixed up his name with Grant Haist, then didn't even get HIS name right :<(. The article is now corrected. Donald Qualls work formulating a monobath from easily available photo chemicals is a really neat piece of work.
By jking - 10:10 PM, 01-28-2005 Rating: None
I painted the inside of the tin and the tin lid black, both to reduce reflections, and because the monobath will corrode the tin plating the first time it is used (I learned that one the hard way). The paint seems to serve as a sufficient light trap around the lid. I put black book binding tape on the hinge side to cover the opening at the tin hinge. It is flexable enough to last at least several photos.
By MikeS - 09:09 AM, 06-10-2005 Rating: None
All this talk of pinhole cameras made me try something. I took an old Kodak 4x5 100 count sheet film box, and made a quicky pinhole camera! Don't think I'll try using it as a processor too tho! Once it gets light outside I will try it out and see how it works!
Talk about the ultimate analog spy camera.... Thanks for the article, this has to be done!