Here is the data on the AT8RC that Roland requeste

Hi Roland,
A friend ran an exposure for me through CCD Inspector to get the data you requested. Here is the result of this. Seeing was not great, it was about a 3 on a 5 scale, showing on the Clear Sky Clock as average.

The exposure (10 minutes at -5c) was not of an open cluster so only 304 stars were used. It was one exposure of NGC6888, so not perfect for the test, but it was the best that I had. The Image Scale was .95" with this exposure.

I am not sure how good this indicates, but my friend said that it was very good. I am not that knowledgeable about this unfortunately.

Attached Image:

Hi Floyd,
Next time do a star rich area on a night of good seeing, no galaxies or nebulae, subtract a dark, and time your exposure so that most stars aren't saturated.
That will yield more valid data.
I'm curious to see how this puppy performs.

dan

Interesting results. I've never used CCD Inspector so I don't know how that correlates with Maxim DL. With Maxim on a good night an 8" refractor will get around 1.2 arc sec FWHM and a 6" around 1.5 to 1.6 arc sec. But again I don't know whether that is measured the same way as CCD Inspector. I'll have to dig out some of my Meade 10" shots from 2 years ago and see what that scope was able to accomplish. I know it wasn't as good as the 6" refractor, not even close.

Attached image is resolution of an 8" EDF refractor at 1 arc sec per pixel (1.13 arc sec resolution on that night)

Rolando

Attached Image: