I would recommend Phil Davis's Plotter/Matcher software which is 
available in Mac asnd DOS versions from Darkroom Innovations. I have 
used both and warn that while the Mac version works very well, the 
DOS version is rather buggy. They say there will be a Windows version 
someday.
Graphs can also be created using most spreadsheet software. I 
would guess that some if not all of the calculations that Phil's 
program performs could be done in a spreadsheet. 
Darkroom Innovations phone number is (602) 488-5117. They can be 
found on the web at: http://www.darkroom-innovations.com/index.html 
Cheers,
Keith
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Keith Schreiber, Rights and Reproductions
Center for Creative Photography, University of Arizona
PO Box 210103, Tucson AZ 85721-0103
Fon: 520-626-5164  Fax: 520-621-9444
Email: keith@ccp.arizona.edu
WWW: http://www.ccp.arizona.edu/ccp.html
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