Resolution Target - Air Force PDF File?

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I have (12,000 miles away) a printed sheet of paper that is some sort of resolution target. I seem to recall it had something to do with the US Air Force and looks somewhat like an old TV test pattern. It has a series of lines and resolution levels.

Now that I actually need it to play with an old lens on the other side of the world, I don't have it and cannot recall the name of it or where I downloaded the PDF (I believe) file that I printed to get it.

Any ideas?

Thanks, Richard

-- Richard Rankin (rpr@superlink.net), December 27, 2000

Answers

Hi Richard, The following link may take you to the resolution information you are looking for. Best wishes to all for the New Millenium John

-- John (jcr@jcr-cameras.com), December 27, 2000.

What you are thinking of is probably the 1951 US Air Force test chart. It is available on the net as a Postscript file, for example as http://www.photo.net/photo/optics/USAF1951.ps on the Optics section of photo.net, http://www.photo.net/photo/optics/index.html

-- Michael Briggs (michaelbriggs@earthlink.net), December 27, 2000.

Richard -

Another possibility is to create your own resolution target(s), even if you want to base them on the ones on the page referred to by John. All it takes is a computer, a good drawing program (Macromedia FreeHand, Deneba Canvas, and Adobe Illustrator come to mind), and a good laser printer (probably 600 dpi minimum. Use the draw program to "reverse engineer" one of the items on the page John mentions, or create your own resolution target(s).

Another alternative that may provide some testing is to use a small program on the Macintosh called Siemensstern, which produces an image similar to the Figure I-5: Sector Star Target on the page John mentions. All you do is select the number of segments, and print the page on a good laser printer.

Ciao.

Alan Agardi

-- Alan Agardi (alanagardi@sprintmail.com), December 27, 2000.


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