Re: [ATM] Identify Large Schneider Lens?

[Jarvis Krumbein <jkoptic@juno.com>]

David, the lens is probably intended for some kind of copying application
(1 to 1 image to actual size) and is probably not useable for
astrophotography.  It will only be well corrected for 1 to 1 copying. 
It's possible that the moveable element is for fine tuning the size ratio
in actual use.

Jarvis Krumbein

On Fri, 17 Mar 2006 11:02:26 -0800 "David Sleeter"
<d.sleeter@adelphia.net> writes:
> Hi Folks:
> 
> I have a large Schneider lens, and I'm wondering if anyone can 
> identify it.
> http://members.aol.com/semgallery/Slens.jpg
> 
> The optimization is apparently adjustable. When I rotate an external 
> ring, I
> can see one of the elements inside move. At one end it says 1:1, but 
> there
> are no markings at the other end. I'm guessing it would be infinity?
> 
> There's an internal iris diaphragm that's adjustable from F5.6 to 
> F11, but
> there is also a stop, and the stop is currently set to limit the 
> range from
> F5.6 to F8. I do not know how to reset the stop.
> 

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