Quote:
Originally Posted by Wavytone
Actually you should consider using what Questar chose to mate with what is arguably the finest planetary telescope - Brandon eyepieces, from Vernonscope. You can buy these without buying a Questar.
The Vixen LV's in the range 4-25 mm have a 45 degree field of view.
HOWEVER, FoV is not really the issue here - for a fine planetary eyepiece - as Suzy correctly indicated - the priorities are CONTRAST and lack of COLOUR, and to that I'll add SHARPNESS on-axis. A huge field of field of view is not a high priority.
Secondly the attributes that make a fine planetary eyepiece effectively eliminate everything from Televue - Plossls, Naglers, Ethoi and Radians included.
The point is to have as few elements as possible, as few glass-air surfaces as possible, and preferably MgF coatings.
Brandons have just 4 air-glass surfaces, and have MgF coatings, and this is one of the reasons why Questar use them - over all others.
Likewise the TMB SMC's have just 2 air-glass surfaces, and MgF coatings, for half the price of the Brandons, and a better range to match Suzy's scope (the shortest Brandon is 8mm).
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Suzy also indicated good eye relief and over 50deg field.
I believe Brandon now make a 6mm but the eye relief is very short and AFOV not greater than 50deg. Clave used to make a 5mm true Plossl with 48deg AFOV and would be a superb choice if you could find one secondhand, (eye relief too is short).
For pure viewing comfort a 20mm eye relief eyepiece such as the Radian should not be underestimated and viewing comfort can greatly assist in seeing finer detail as can good tracking. The image in a Radian does not distort as the images drifts from centre to edge if used in a non-tracking telescope. The Nagler zoom too has only 5 glass elements and gives remarkable performance on planets and is a joy to use simply for its zoom ability.
Note. Brandons are $235 USD. Another option is the Takahashi LE 5mm which has long eye relief. Not sure of the cost.