Quote:
Originally Posted by A1
Hi Knigtrider,
I use the 2" 30mm GSO SV with 68 degree AFOV all the time as a finder and wide-viewer in my 10-inch and 12-inch f5 Dobsonians. The image quality is absolutely amazing for the price.
GSO also makes 20mm and 15mm versions of this SV (superview) 68 degree eyepieces in 1.25 inch.
Andrews sometimes sell them. About USD$45 each online at AgenaAstro (dot) com
This is the best bang for buck in the price range you indicated. GSO products seem optimised for fast Newtonians.
You can distinguish the difference between coma and astigmatism by rocking the focus. Astigmatism causes the oval shaped stars at the edge of field to change direction by 90 degrees when rocking focus from in-to-out.
Best wishes, Jason
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Thanks Jason,
I actually had a 15mm SV that I sold earlier this year. I found it to be less tolerable in my scope than the 30mm. Distortions started at about 70% out for me, and just didn't look very good when being used on GC's. It performed a lot better F/8 than at F/4.7
Thanks for the tip. I'll give it a shot one the 30mm.
Thanks Jeremy also for the suggestion. I had a look at it, but aren't really looking for another 30mm. I ended up buying a Meade HD-60 25mm. It had plenty of good reviews for scopes similar to mine. I haven't a had a go at it yet though