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Hi,
after having to wait well over a week for a clear night where I was not working, I finally managed to test this combination on my 8" f4 GSO Newtonian. At this point I am unable to recommend the Rowe Coma corrector. It is incredibly (excessively?) sensitive to collimation. Prior to use I collimated the scope using a set of Catseye tools to get what I thought was perfect collimation. This level of collimation is sufficient that with the Baader MPCC I already owned, I get perfect stars in all four corners of a QHY8 frame. At no point was I able to achieve this with the Rowe corrector. At first I wondered if the extra length was causing focuser sag that was changing the effective collimation, so I tried imaging first on one side of the meridian, and then the other. However there was no change in the star shapes between frames indicating that the focuser was not shifting appreciably. At this point, I believe the only way to salvage my whole imaging system is to buy a set of the new dual hole Catseye tools to see if their increased accuracy cures the imaging problems. Not sure yet whether to do that as it may be good money after bad. Imaging with cheap newts seems very problematical, and I guess you get what you pay for..... Imaging with refractors is sooooo much easier and more relaxing.
The Off Axis Guider was much easier to use than I expected. I managed to get a guide star everywhere I pointed the scope using 3 second exposures on a QHY5 - not the most sensitive of guide cams. I was able to get round stars (in the center of field of course!) with a 30 minute exposure, so that at least works.
I haven't posted copies of images since there is nothing to really show off..... Buyer beware.
cheers
Gary
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