Normally I calculate my exposure times for pinhole photography by guesstimation, especially when I use my converted Gevabox or Agfa Clack. But sometimes I want to measure the light more securely. When I didn't bring my real light meter, I use the Pocket Light Meter app on my iPhone (also available for android). This app has a minimal ISO setting as low as 0.8 and maximum aperture as high as f/512. This makes this app very usefull for pinhole photography and for using photo paper as a negative. And it is very accurate too. I compared it with my digital camera.
The app is free (with a small add in the top of screen) or only $1.00 for the add free version.
See for more info:http://www.pocketlightmeter.com.
The app has some nice features. It shows also the EV values, if desired. And you can "HOLD" the screen - holding your last reading. You can also take a small snapshot to log the used settings - and add some notes.
This is an example of the snapshot (jpg, 150 KB):
The app can also sync with Dropbox to save the snapshots for later. Coming back home you can check the snapshots to see what settings you used when & where: the file name contains a date & time stamp. Here you'll find a small test of this app:http://thephotobrigade.com/2012/06/p...-by-c-s-muncy/
A nice app for pinhole photography!
"Have fun and catch that lightbeam"
Bert from Holland