If you don't have (or use) a light meter, Richard Koolish's clever mechanical calculator can help you select an exposure time for tiny aperture (pinhole) cameras, which require lengthy exposure times.
These disks are designed around Ilford's version:
http://www.ilfordphoto.com/Webfiles/2011106152612113.pdf
Which is attributed to Mr. Koolish, but freely downloadable (and included in the source files for this thing).
...but there are others:
http://www.rahji.com/pdf/koolish.pdf
http://static.freewebstore.org/templates//79100/myimages/pinhole_camera_exposre_calculator.pdf
http://www.rahji.com/wordpress/2007/05/12/pinhole-exposure-times/
ATTENTION
This work is licensed under the Creative Commons - Attribution - Non-Commercial license. This license applies only to the files and documents available for download from the Thing Files section of this Thing.
All other related content (photographs, videos, and verbiage such as contained in "Description" or "Instructions" ) are excluded from this license. with all rights reserved, unless specifically available for download This notice constitutes a clarification, not a change, to licensing for this design.
2011106152612113.pdf | 385.3KB | |
PEC_1.stl | 18.2KB | |
PEC_2.stl | 19.0KB |