Use the following tools and instructions to make your own zone plate, photon sieve or pinhole sieve. The tools and instructions are included in the zip file below. You will also need a high contrast B&W film and a high contrast film developer.
Once you have downloaded and unzipped the file, follow these instructions:
/F 75 def % change the number to whatever focal length in mm you wantto
/F 80 def % change the number to whatever focal length in mm you wantNote that 75 is the value the file has after being downloaded, once you have changed it and if you save the edited file onto itself, it will keep that new number until you change it again. Feel free experimenting changing the other values as indicated in the Postscript file itself.
You will need a program capable of printing Postscript files. I used PDFCreator, this program takes the *.ps file and convert it to PDF, that you can easily print. PDFCreator is free. Photoshop is also capable of printing *.ps files. I have also been told that a Mac computer recognizes postscript (*.ps) files without the need of any extra application.
This spot meter circle has a diameter that for each camera model should be indicated in its User's Guide Manual. We could use a compass to draw a circle on a piece of paper that has a diameter equal to the diameter of the spot meter circle in the viewfinder times the magnification used to print the "lens" and then place the camera at a distance such that the spot meter circle on the view finder overlaps it exactly. For example, in a Nikon F801s, also known as N8008s, the spot meter circle is 3.5mm in diameter, if we have used 30 as the magnification to print the "lens", we would need to draw a circle 105mm in diameter (3.5x30), place this circle on the same place we would later place the printed "lens" and make the spot meter circle in the viewfinder match exactly this 105mm circle.
Copyright © 2021 Guillermo Peñate • File was last modified: November 13 2014 13:49:29.