To expose film correctly we need to figure out what aperture our pinhole is then we can use that info along with the ISO of our film to determine what the shutter speed should be. Again I used the info from the site http://silverbased.org/pinhole-101/
and this one http://mrpinhole.com/calcpinh.php
to determine my aperture size, and from those I think my pinhole's f stop is around 90.
So to take photos I simply use my hand held light meter, plug in the ISO of my film and take a reading (if you don't have a light meter you can use your camera to do the same thing) then I can refer to the numbers below by Dr Evan Reece (another NZ photographer and pinhole maker, website here: http://www.ejreece.com/
) to figure out an approximate exposure:
Aperture/F stop1.2 1.4 2 2.8 4 5.6 8 11 16 22 32 45 64 90
(the approximate aperture of my camera)
Shutter Speed/Exposure Time1/1000 1/500 1/250 1/125 1/60 1/30 1/15 1/8 1/4 1/2 1sec 2sec 4sec 8sec 16sec 32sec 1min 2min ...etc
Example: You meter F.11 @ 1/60 of a second
To get the exposure simply count the steps from the aperture you metered (in this case F.11) up to that of your camera (in my case F.90) so for this example there are 6 steps from F.11 to F.90, then you simply count that same number of steps on the exposure scale so in our example we start at 1/60 of a second and count up 6 steps so we know the exposure time should be about 1 second.
When you come to the end of your film simply switch the winder from one hole on top of the camera to the other and rewind the film right back to the beginning before taking the camera apart to remove the exposed reel.