81/4 inch f4.5 Xerox lens mande in England by Rank Taylor Hobson

81/4 inch f4.5 Xerox lens mande in England by Rank Taylor Hobson

Would any one know anything about this lens. Is it a portrait lens or as I
suppose a copy machine lens?
I find some of the info I can glean somewhat sketchy.

Re: 81/4 inch f4.5 Xerox lens mande in England by Rank Taylor Hobson


"otzi" <xx@xxx.xxx.au> wrote in message
news:47eb6074$0$26468$afc38c87@news.optusnet . com .au...
> Would any one know anything about this lens. Is it a
> portrait lens or as I suppose a copy machine lens?
> I find some of the info I can glean somewhat sketchy.
If it says Xerox on it its obviously a copy machine lens.
These are typically Plasmat types optimised for unity
magnification. Also, they typically have a limited range of
f/stops although you can sometimes remove the mechanical
stops in the iris mechanism.
The color correction depends on the kind of copy machine
it was intended for. Some older Xerox machines used blue or
green light and the lens may be optimized for it. Newer
machines are panchromatic or color and the lenses must be
well color corrected.
The performance of these lenses at infinity may be pretty
good if they are not used wide open.
Taylor-Hobson is a known for manufacturing very high
quality lenses.
About all I can say is to try the thing and see what it
does.


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Richard Knoppow
Los Angeles, CA, USA
dickburk@ix . net com . com