Thanks for your reply. Your answer inspired me and I found that I already had the answer in no less than three photography books (I should have looked before I posted!). One being the 1958 edition of the Ilford Manual of Photography. Attached is a scan from this excellent book showing a spectrograph. Baker also has construction details for one.
Diffraction gratings and lenses can be purchased very inexpensively from "The surplus shed". http://www.surplusshed.com/
These companies sell step wedges.
http://www.stouffer.net/TransPage.htm also http://www.tiffen.com/Kodak%20Profes...%20catalog.pdf
Any recommendations on the part number of the step wedge that would be most suitable?
Last edited by Emulsion; 10-27-2007 at 05:14 AM. Click to view previous post history.