Classic: The 25 mm Kellner that came with my good old Edmund Scientific 3 inch reflector. That eyepiece and scope are what I received for Christmas 1968 as an eight year old. It opened up the moon, M81, M82, etc. etc. to me and it was all that I could afford for some time. So, even though it is no longer used (but I still have it) - it is still my favorite because that is what got me started. Clear skies, Dale.
-----Original Message----- From: utah-astronomy-bounces@mailman.xmission.com [mailto:utah- astronomy-bounces@mailman.xmission.com] On Behalf Of Chuck Hards Sent: Friday, December 09, 2011 9:09 AM To: Utah Astronomy Subject: [Utah-astronomy] Favorite eyepieces
What are your favorite eyepieces?
Two categories.
1. Modern. Designed and marketed from about 1985 to present. This category includes Televue for our purposes
2. Classic. Old-school designs and makers, up to about 1980.
I'll start.
I have no modern eyepieces worth mentioning.
My favorite classic eyepieces:
1. Universtiy Optics 32mm Wide Scan. With an 82-degree FOV in a 2" format, it's given me some incredible views of extended DS objects.
2. University Optics 16mm Wide Scan. Same design with half the focal length, in a 1.25" format. The eye relief is on the short side, but the views are outstanding.
3. University Optics 40mm 7/70. 70-degree FOV, 2" format, another great low-power eyepiece.
The above 3 eyepieces work best with objective f-ratios of 5.5 and slower, from my experience. I also have the modern UO 25mm MK-70 (misspelled "Koning" on the barrel, lol) but it is not of the same caliber as the classic UO wide-field designs. Avoid it.
4. My old mixed set of Jaegers and University Optics classic Japanese-manufacture orthos. I have them in 4mm, 6mm, 7mm, 9mm, and 18mm. Narrow 40-45-degree FOV by today's standards, but a wide field isn't much of a bonus on planetary targets and double stars, my usual application for these oculars. Extremely sharp resolution, and they work well with most f-ratio objectives. Tiny eye lenses and short eye relief as you approach the higher power end of the series, but sharp all the way. I don't need my glasses at the eyepiece (my astigmatism isn't bad in my dominant eye) so the lack of eye relief isn't an issue.
5. My old set of U.O. Erfles. 16mm, 20mm, 25mm, and 32mm. A reasonably wide 60-65-degree FOV (except the 32mm which is closer to 50-degrees due to the restrictions of the 1.25" format). With ojectives of f/5.5 and slower, they are good performers and the edge distortions minimal. It's also fun to say "Erfle". ;-)
Using these old eyepieces with modern fast mirrors means a coma corrector is required. I have the orginal Lumicon 2" coma corrector which works well down to about f/4, but was optimized for f/4.5. But they all work very well with SCT's (f/10), and my mid-size Newts operating at f/5.6 up to f/8, and the innumerable small refractors that I like to challenge my visual skills with when observing in the backyard.
What are your favorite eyepieces of today and yesterday?
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