MAKE: Blog: $0 digital pinhole camera
http://blog.makezine.com/archive/2009/03/0_digital_pinhole_camera.html?CMP=OTC-0D6B48984890

Stupid title

how to make your digital camera into a pinhole camera!

iris. This pinhole ensures that the light which reaches any position on the exposure surface originated from a single direction; as the hole diameter approaches zero, the possible light source for a point on the exposure surface becomes an increasingly narrow cone, approaching a straight line. The result is that if you make the hole small enough, you can capture a very wide depth of field, with objects both near and far in focus. The small hole also reduces the amount of light that reaches the exposure surface, in this case a CCD, so you need to compensate with a very long exposure time. It's a perfect tool for capturing slow movement over time, or taking rich photos of still scenes that require a huge depth

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