Pinhole / Zone Plate / What's the difference?

[Jim Moore]

Could someone please tell me what the difference between a Pinhole and a Zone Plate is?

Thanks!

Jim

 

[removed account4]

hi jim

about 1/2way down this page you will see a zone plate.
http://www.pinholeresource.com/agora/agora.cgi
it looks like a "bullseye" , and can give you a beautiful glowing image.

if you have a lubitel 166 ... ( the tlr lomo )
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&category=710&item=3835662213&rd=1
the zone plate will fit perfectly in front of the shutter.

pinholeresource sells zone plates and laser - drilled pinholes

sorry i didn't really answer your question ..
i was going for the picture is worth 1000 words

 

[glbeas]

Ed Sukach's links to diffraction related articles explains things very well in this thread.

(there was a url link here which no longer exists)

 

[cnmne]

Practically, a zone plate is faster than a pinhole, but less sharp. Also, the zone plate imparts a kind of "glow" to highlights. A zone plate has an ideal focal length, thus can be focused for a particular subject distance, but focusing is not absolutely necessary to produce a usable image.

Some examples of my zone plate images: Dead Link Removed