RE: ATM Secondary de-center

["Mel Bartels" <mbartels@efn.org>]

>>>
pointing errors will result.  Consider the case of a
small Alt Az, say 12" f5 with a 4mm offset (from
desired). At that focal length, 1 degree is approx' 1
inch at the focal plane. 4mm therefore, translates to
+/-10 minutes of arc. A significant figure if you are
slewing around the sky trying to acquire dim galaxies
on your Kaf0400.
     Perhaps worth keeping in mind if you are making
an imaging machine out of your trusty Dob...  
(perish the thought)
       Clive.

<<<


Luckily there is software to correct for that now!

Mel Bartels