Note the 16mm T5 Nagler is closer to being parfocal with your other two. See
http://www.televue.com/engine/TV3b_p...4#.U2h3QYGSy5I Column F.
However the 17mm is a 2" version and has a big eye lens and is good for eyeglass wearers whereas the 16mm is not. Both are quality eyepieces though. An alternative would be to replace your 27mm Panoptic with a 26mm T5 Nagler which happens to be close to Parfocal with the 17mm T4 Nagler. The 26/17 is a very nice match and both have 82 degree apparent fields. The 26mm T5 Nagler also has a bigger true field than the 27mm Panoptic and slightly less exit pupil.
Note though the thickness of your 2" to 1.25" adaptor will come into play when swapping eyepieces that are parfocal. I personally like the 26/17 combination.
Quote:
Originally Posted by stephenb
Thanks Adrian and MortonH for your quick replies.
I'll shoot them an email shortly and see what they can do....
On a broader topic I've been considering expanding my EP kit (from one lonely EP) and creating a kit of 3.
Thanks to some advice from Bintel I am now looking at this range and the magnifications based on an 18-inch f4.5:
27mm TV Panoptic 68° - 76x mag
17mm TV Nagler 82° ($379) - 121x mag
9mm YV Nagler 82° ($499) - 228x mag
Now checking some comparisions to the ES range I come up with:
ES 6-Element 28mm 68° - 73x mag
ES 9-Element 14mm 100° - 146x mag ($339)
ES 9-Element 9mm 100° - 228x mag ($399)
ES is less expensive.... but Imay have to factor in shipping which will close the gap slightly. Thoughts on this hyperthetical, 3-piece, all-round EP kit?
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