This is a calculator for working out the exposure timing for a pinhole camera, based on the light-meter reading from an SLR Camera. For each step all the fields in that step are required along with the fields in the previous steps. This is with the exception of the two ISO fields which are optional. However, if the ISO fields are not filled in a default value will be assumed and so the results for 'Exposure Factor' and 'Pinhole Timing' will not be as accurate as it could possible be. You will be warned if this is the case.
Step 1 - Pinhole Camera Aperture
Focal Length (mm)		Pinhole Aperture
Pinhole Diameter (mm)
Step 2 - Exposure Factor
Camera Aperture (f/)		Exposure Factor
Camera ISO
Pinhole ISO
Step 3 - Calculate Pinhole Timing
Camera Shutter Speed (s)	/	Pinhole Timing