RE: [APML] Taurus cameras

["Jon Kolb" <jkolb@datawest.net>]

Hi Bobby,

> Anybody left out there who is familiar with the old Taurus 
> cameras (C2)? Robert Hoyle knew them but I haven't seen 
> Robert post in a long time. So did Peter Ceravolo. Is there 
> an easy to way to calibrate one of these to exact critical 
> focus with one's SLR? What I have in mind is to compose/focus 
> with my F2 then switch to the Taurus. Bobby Middleton

I don't know anything about this camera, but if it has a pressure plate
like most cameras, you can measure the distance from the lens mount
flange to the pressure plate with a digital depth micrometer on both
cameras.  If they're close, you may be able to adjust one or the other
to make them the same.  

Alternatively, you could rig up a plunger-type micrometer on your
focuser like Chuck has done.  This device could be used to either move
the focuser the required amount to compensate for the difference in the
two cameras, or by taking successive readings and test shots, you could
use it to return to the correct focus point next time out.  The latter
approach always has me worried about thermal changes, especially with a
reflector, and of course you'll have to do it all again after you
collimate.

Another option is to get a Mitsuboshi KEF and have it calibrated to your
Taurus.  If the difference isn't much between that and the Nikon, you
should still be able to compose using the slightly out-of-focus F2.  You
can send the Taurus to Hutech for calibration, or you can buy your own
depth micrometer.  I bought my own for use with my Pentax 67s, since I
want to be able to adjust the KEF myself if it ever shifts.  A good
digital depth micrometer is not cheap, but a cheap one probably isn't
very good.

Hope this helps - sounds like a fun project.

Sincerely,
Jon Kolb
Adventures in Astrophotography
http://home.datawest.net/jkolb/
jkolb@datawest.net
719-330-3160
 



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