[MrB (Simon)]

Originally Posted by skysurfer

But how should I mount the Televue Genesis on the Astrotrac ??

As you have found, fitting a ball head is easy. Mounting a scope is not.
The trackers are designed for camera's, hence the easy attachment of a ball head.
Astrotrac though has accessories available for mounting scopes, ofcourse they increase the overall cost and add weight.
First you would need the Declination head: http://www.astrotrac.com/Default.aspx?p=head
Onto which you can mount dovetail plate adaptor.
An example is this one: http://www.firstlightoptics.com/astr...010-head-.html

I'm not using a dovetail. I have a solid 20mm thick by 50mm wide by 200mm(or 250mm?) long aluminium bar bolted to the head which has various sized holes(some are threaded) that allow me to attach tube rings and ball heads and whatever else I want. I think this is much more rigid than any dovetail.

And isn't the $220 polar scope a Requirement ?

For short focal lengths, not really. You can get it close enough by eye and a bit of fiddling.
For longer lengths(scope), yes, you will need it.
However, Roger Groom (rogerg) has an attachment that holds a laser pointer and he uses this to align. This should work out to be a much cheaper alternative.

I see some sketches of the sky in the user manual with the surroundings of both poles (resp Crux+Achernar and Ursa Major+Cassiopeia). Is there a reticle supplied ?

What you see in the polar scope is as per the manual.
I have never used the constellations and stars as etched on the screen, I just set the centre (cross point of lines) as close to the correct offset from Sigma as possible. This is usually good enough for 5 to 10 min subs for me.