Pinhole with medium format and beyond
Film is still available in sizes greater than 35mm, mainly 120 and 5x4. Both of which give increased quality to a pinhole image. Although I haven't had a massive amount of experience in this area there are a few things I have learned which may be of use.
One thing to bare in mind is to enable good depth of field in the foreground, you may need to raise the subject so the pinhole is close to the 'ground'.
There are a few great 120 pinhole cameras out there but, as with 35mm, many poor ones usually due to the pinhole being too far from the film plane to allow a 'quality' image. Cameras such as the Holga are great fun but wont allow you to get the pinhole close enough.
You can think of there being a 3:1 ratio of projection from a pinhole to film plane. To find the closest height for the pinhole, measure both corner to corner distances, add together and divide by six. This is the ideal (maximum) height of the pinhole and will project an image on most of the film area.
6x6 = 2cm 6x9 = 2.5cm 12 x 17 (5x4) = 4.5cm
Old 120 cameras
The trickiest aspect of 120 film use for pinhole is enabling the film to be wound on. One fun, if drastic way to get over this is to find an old 'Box brownie' or bellows camera and 'adapt it' for pinhole use.
All cameras are different. If its a Bakelite camera, give up. If you have a box brownie make sure it is one of the common ones then, if it is and is saw-able, its time to get the saw out!
Some old bellows cameras are a format larger that 120. If this is the case you will need to get a second wind on spool and adapt accordingly! The handy thing with bellows cameras is the lens and bellows are usually easily detachable.
120 film backs
These are a lot cheaper than they were. I find the best is the RB67 film back which has the advantage of containing a dark slide. You will have to build your own pinhole mount on the front which is a bit tricky but a steel sheet housing from the lid of an old Quality Street tin along with some black glue gun glue will work.
5 x 4
If you are lucky enough to have a 5x4 camera you will need to get a set of 'bag bellows' to enable the pinhole to be close to the film plane.
Harman make their own (very pricey) 5x4 pinhole camera, the Titan. If you do find yourself with one, you may find it works better by adapting it by making your own pinhole and positioning it closer to the film plane (get the saw out again!).
Now I love Harman - Ilford as much as the next person but I have a problem with the Titan and using an existing 5x4. Firstly nthere is the price, but also it is designed for use on a tripod which aint what I do as it eliminates the depth of field in the foreground. (I wonder why they didn't get me to review it!)
It also doesn't fit in my mouth (almost but not quite!)
One of the most rewarding as well as bewildering approaches to pin-holing is imaging on the inside of a cylinder. Although this can be done with photographic paper a Pringles box (Cut down to 8 inches high) can take a sheet of 10 x 8 film. A toilet roll inside can take 5 x 4.
Have a look at my instructions on the black and white photo paper section for making the tubes. The images below were taken using 5 x 4 and 10 x 8 film.