See http://www.optikos.com/ealing/eros-sira_mtf.htm and
http://www.optikos.com/Pdf_files/how_to_measure_mtf.pdf
Tom
On Monday, December 17, 2001 at 13:59, Hans van Veluwen
<olympus@xxxxxxxxxxxxxxx>
wrote re "Re: [OM] FYI - all the 35 mm lenses tested by pho" saying:
> : It's not possible to test performance at infinity by using an extension :
> between lens and body. The focusing scale would say "infinity", but that :
> scale is only correct when the lens is used without extension. The testing :
> done would actually be for some other reproduction scale. Still somewhat :
> relevant for our old lenses, but nearly useless for lenses with internal :
> focusing. : : There are two ways I can think of that would make testing at
> infinity possible: : a) Parallell incoming rays, checking point size in
> focal plane. : b) Point source in focal plane, checking the spreading of the
> light bundle : coming through the lens.
>
>
> According to http://www.photodo.com/art/Unde7.shtml they've done all their
> testing on 'Hasselblads Ealing MTF equipment'. Does anybody know what this
> is? Some kind of optical bench, I suspect?
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