Quote:
Originally Posted by DavidTrap
What is the difference between images 2 & 3 - ??spacing??
Keen to see what AP telecompressor is like.
DT
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David,
the visual difference is of course in degrees of coma and the technical difference is between the commercially available Lepus device and the prototype of the replacement. There is no difference in the spacing between the two devices and the CCD but there is a difference between the device and the correcting element in the EdgeHD - that being that the one with less coma is much closer to the corrector by as much as 20mm or so. Optically, I think the 2 are identical. The difference is only in the way they are each mounted onto the scope.
Tim, the mount I used for these is a Losmandy Titan. But even so, there is a bit of something going on in all these images that is probably a bit of balance and perhaps a bit of tracking - there is a general tendency to egginess running top right to bottom left. Haven't figured that one out yet.
But the big news is that I have now finished the series with the AstroPhysics reducer and have added that image to the original post.
It is 30 minutes of 3 minute subs.
Makes a heck of a difference - to the point where I'm tempted to say that there is no visible coma remaining - at least out to the limits of my QHY8.
I'm chuffed.
Peter