# Engineering 1000 mm multiple pinhole lens

• 12-20-2010, 09:33 AM
Mustafa Umut Sarac
Engineering 1000 mm multiple pinhole lens
I want to experiment with multiple circular random placed pinhole lens. My intention is to build a 120 camera with 1000 mm lens.
I want to drill hundred or more pinhole on to large circular brass thin plate.

How can I decide the plate diameter , lens film distance and the count of pinholes , their diameter and placement.
What is the result of random placement or an regular ?

And how can I be sure every pinhole on large circular plate -15 inches diameter may be -would be effectively cast a image on 120 film 66.

What is the engineering way to accomplish this ?

Thank you ,

Mustafa Umut Sarac

Istanbul
• 12-20-2010, 09:57 AM
Jim Jones
Go to http://pinhole.stanford.edu/zp.html for a brief discussion of pinsieve.
• 12-20-2010, 10:33 AM
RalphLambrecht
Mustafa

The last page of this may also help:

http://www.waybeyondmonochrome.com/W...ographyEd2.pdf
• 12-20-2010, 03:00 PM
Mustafa Umut Sarac
http://4.bp.blogspot.com/_l5YNpRMm2e...pic_orange.gif

How can I engineer this pin sieve lens for 66 and 1000 mm ?

Umut
• 12-20-2010, 03:19 PM
RalphLambrecht
What do you mean with engineer? Are you asking how to make it?

Easy. Create a negative image of it (see attached), print it black-and-white at 50x scale, and then photograph it on high-contrast film at a distance of 50x the focal length. Use the piece of film as your photo-sieve lens.
• 12-20-2010, 03:27 PM
Mustafa Umut Sarac
Random Discrete Fresnel Zone Plate is the above lenses name.
Ralph , I know how to photograph something but I am sure above lens is not engineered for my purpose.
I am asking the formulas for design similar plate for my work.

Umut
• 12-20-2010, 04:49 PM
RalphLambrecht
Mustafa

Send me a private email, and I'll share the math with you.

info@darkroomagic.com
• 12-20-2010, 06:06 PM
AgX
I am lost, as in this thread random and regular pinsieves are mixed up.

And to my understanding the random one is only appropiate to X-ray imaging.
• 12-20-2010, 06:32 PM
Mustafa Umut Sarac
Random one is for decrease the higher order aberrations. There is no limit at the formulas to keep it for x ray. You enter the wavelenght and it gives the pin sieve.
Ordinary zone plates are the subject for x ray imaging but ordinary cameras uses them also.
I think x ray technology comes from the x ray lab at germany and their problem was not making ordinary camera lenses.