[ATM] RE: Dob vs Eq mount

[tkrajci at san.osd.mil (Tom Krajci)]

From: "Richard Brodie" <richardbrodie@optusnet.com.au>

>My
>main criteria is compact travel...

Then I recommend a dob first, and perhaps a split ring next, or a
compact fork third.

>I am about to start work on the design of the mount and I'm intrigued
by
>what looks to me to be an obsession with dob mounts rather that
>equatorials for the miminalist alu telescopes being constructed.

>Is there a particular reason(s) for this?  

Yes, absence of cantilevered loads in a dob mount.  Presence of
cantilevered loads in just about any other mount type.  Absence of
cantilevers is a good thing in my design notebook.

>...I would like to be able to do photography, even though visual
>observing will be my most common way.

You have just stated a very different design requirement than the one
you first mentioned above.  This will require much better performance
from the mount/drives for photography.  You can accept and tolerate
lower standards in a visual mount...not so for photography...especially
long exposure and long focal length work.  Good luck.

Tom Krajci
Tashkent, Uzbekistan


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