Quote:
Originally Posted by sassan
. I am wondering why the sharpness is not any better. Was the pin too thick? 0.3cm look that way to me but then for indoor light it sure was a good choice. Or may be your distance form sensor was too close.
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Sassan
See attatched pic of my pinhole. I think you may have miss read the hole dimension. In pinhole photography the size of the hole is relative to the focal length and should not be confused with adjustable f stop in your normal lens. A couple of examples - my 0.3mm hole from a fine sewing needle = optimal focal length 75mm, my first attempt with a domestic pin at 0.6mm = optimal focal length 300mm. Focal length in this case being the distance from the pin hole to the sensor plane. My couple of experiments showed +/- a few mm was of no consequence. Scroll to the bottom of this link to get the idea.
http://home.online.no/~gjon/pinhole.htm
On the subject of fall off of sharpness then I have attatched a crop of a set of images from my test of the diffraction limit of the D2X. f8 is optimal, f11 is OK then things start to go downhill. So looking at that image and given my reckoning of the f stop range to the pinhole of 0.3mm -f8, f11, f16, f22, f32, f45, f64, f90, f128, f192 plus about 1/2 stop to f229. Link to the original thread on the subject
http://www.worldphotographyforum.com...ead.php?t=1186
Don
01-11-07, 20:34
