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Originally Posted by Starkler
As you have the same scope as I , my opinion is that a 7 or 8mm eyepiece isnt short enough to get to a good planetary magnification. I have a 7mm ortho that I would gladly trade for a 6mm.
IMO the ideal workhorse planetary ep would be a 6mm, but there are very few sold at this focal length other than the TV Radian.
When the TMB/Burgess 6mm becomes available I plan to buy one.
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Geoff/Mike,
I have the 7mm and 10mm Pentax XW's and 5,6,7 and 9mm UO HD orthos as my native high power eyepieces. I also have the 2.5X Powermate and sometimes barlow the 14mm Pentax XW in the Powermate for an effective 5.6mm focal length. You really need both a 6mm and the 7mm because of variable seeing and if you can afford it you also need a 5mm for nights of very good seeing. I have many nights where the 5mm or the 6mm will not hold up and you need to drop back to the 7mm, particularly on Jupiter and Saturn. If I was only able to have 1 eyepiece in this focal length range it would be 7mm. 8mm is too short a focal length IMO for planetary work in this scope. The 8mm Vixen LVW is a great eyepiece but you really need a 7mm focal length IMO. The 7mm also does on excellent job for high power work on DSO's. I often stick the 7mm Pentax XW in the scope with my Astronomiks OIII filter and then use Argo to tour planetary nebula. Excellent combo all round for this. Also a great combo to go deep on globular clusters (without a filter of course).
Something else to consider are the Williams Optics UWAN. I have discussed these with Tom Trussock and he rates these very similar to and almost as good as the Nagler T6's at about 70% of the price. So they are definately something to consider (I know Naglers row your boat).
If you are not critical about having an 82 deg AFOV nor worried about the extra size and weight of the 7mm Pentax XW, it is the best eyepiece optically, in this focal length range that I have used and I have used just about all of them. Remember that Comfort (eye relief), Sharpness, Contrast, High Light Transmission and cool colour reproduction are important factors to me in rating eyepiece performance, they may not be so important to you.
CS-John B