Q1: I have a Ken Dauzat extra-heavy duty mounting bar (13 inch long) on order, hoping this will help with the cone error problem on the 10 inch Newt, described below. Should I change the order and make the bar 18 inch long. I feel part of the problem may be optical tube assembly flexure. Q2: Assuming that the Synta EQ6 is inherently overloaded with a 30+lb 10 inch Newt on it, and the cone error cannot be reasonably removed, what does this foretell for: 1) Pointing accuracy 2) Tracking accuracy for astrophotography. I had hoped to use the Atlas 10 inch Newt on the GEM for astrophotography. Since the cone error may not be removed, I am not so sure that it can really be used for this purpose. I can use the 5 1/4" refractor for imaging, which is also described below. Background info: After rebuilding the mounting bar, tube rings and finder holder, I was able to remove cone error down to between 15 to 30 arcsecs (less than one circle width of a Meade 12mm reticule on a 1127mm focal length) for a 5 1/4" refractor (about 20lbs) and a Synta EQ6 GEM mount. But when I tried this with the 10" Newt (30+lbs, 1200mm fl), it was apparent the cone error could not be removed, even using the solid mounting bar (Scopestuff LD75 bar). Just mounting the scope and weights and rolling the scope from the 6h to 18h positions, resulted in the polar finder flopping about 10 arcmins (1/2 the width of the cross-hairs (that are about 20arcmins) in an Orion Altas polar scope reticule). At the 6h to 18h positions, the centered alignment target was moving 3/4 to 1 deg. I tried to remove the cone error, but in the end it seemed to be fools errand. So, I compromised and removed the cone error to a 90-60 arcsecond tolerance - just using the 3h and 21h RA positions instead of 6h and 18h. - Kurt _______________________________________________ Sent via CSolutions - http://www.csolutions.net