University Optics 32mm MK80

Hi all,

I'm tempted to pick up this eyepiece. I've enjoyed every UO eyepiece i've ever laid hands on. My problem is this...i'd like to use this eyepiece in my new 8" SCT, but would also use it as a finder eyepiece in my dobsonian. Does anyone have experience with this eyepiece in a dob?

I'm assuming it will be excellent on axis, but be filled with coma in the outside 20%? That would be OK with me since this is not a Nagler. lol

Another alternative is to be patient and wait for the Paragon 30mm to show up......waddaya think?

Any info or suggestions would be great. I do NOT have the money for Televue, Tak or Pentax-though I wish I did. :-)

Rob C

Here's a review. Didn't seem to have good edge correction in f/6 as the author just called it "acceptable." In your SCT though it should be excellent based on the review.

http://www.cloudynights.com/documents/konig.pdf

btw - I never used this ep, but I do have the UO 32mm 1.25" Konig which does have some edge issues in my f/4.7 with coma in outer 1/3 but minor compared to some others. Used these go for between $75-100. AFOV is not 80 deg though...probably more like mid-50's. Persues Double is gorgeous with this in both my f/4.7 and f/11 scopes.

Rob,

A friend of mine owns this eyepiece. It works very well in his rather one-of-a-kind 20" f/10 classical Cassegrain so I assume it should perform similarly in an f/10 SCT.

However, I'm sure that the 32mm MK-80 would exhibit plenty of field edge astigmatism (not coma) when used with your Dob. (What's its f/ratio, BTW?)

Perhaps, you should look at some of the 70 degree AFOV Erfles and modified Erfles, which for some reason or other just aren't called Erfles anymore, in the 30 to 32mm focal lengths as well.

Dave Mitsky

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Me too!
Particularly when matched with the focal ratios they're designed for.

<< ...i'd like to use this eyepiece in my new 8" SCT, but would also use it as a finder eyepiece in my dobsonian.>>

This does not answer your question about this ep. But have you considered a powered finder for both scopes instead.

Less than well corrected wide field low power ep's as finder ep's, when combined with fast focal ratios, leave me chasing faint fuzzies all around the edges of the field of view. Deep field charts of the area ones searching counter this. But hunting faint fuzzies with fast focal ratios using wide field ep's not design for them can be frustrating.

A 50mm finder makes a great alternative.

I find the Siebert 34 or 36 observatory grade to do very well indeed. New $200 not cheap, but on the few occasions that they show up for sale $150 seems to be the asking price. I picked up a spare on the Auction for even less (to my surprise).

robert cosgrove said:

Hi all,

I'm tempted to pick up this eyepiece. I've enjoyed every UO eyepiece i've ever laid hands on. My problem is this...i'd like to use this eyepiece in my new 8" SCT, but would also use it as a finder eyepiece in my dobsonian. Does anyone have experience with this eyepiece in a dob?

I'm assuming it will be excellent on axis, but be filled with coma in the outside 20%? That would be OK with me since this is not a Nagler. lol

Another alternative is to be patient and wait for the Paragon 30mm to show up......waddaya think?

Any info or suggestions would be great. I do NOT have the money for Televue, Tak or Pentax-though I wish I did. :-)

Rob C

New price from UO is $295 + shipping. Why not just get a used 35mm Panoptic instead. The one I had was great in my 8" SCT and very good in my f4.7 dob with a little softness at the edge, but a pleasing view none the less.
Cheers,

Hi Robert,
Somewhere in this forum a few monthe ago I and others made comment on the 40mm Paragon, the 35mm Panoptic, and the 40mm UO. I also have the 32mm MK UO as well as a couple others including the Siebert 36mm OG. Sorry I'm traveling and can't go into detail as I've got to catch a flight. Shoot me an email and I'll send you more tonight.
CS, Bill