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View Full Version here: : 80° Ultra-wide 15mm ep from My Astro Shop


robagar
22-05-2007, 09:19 AM
I buy a new eyepiece, along comes ex-cyclone Pierre. Coincidence?

Review to follow when the clouds go away...

iceman
22-05-2007, 12:35 PM
I look forward to reading it, Rob!

In the meantime, use it to look at powerpoles in the distance :)

ving
22-05-2007, 01:23 PM
or the neighbours
;)

no, dont do that...

look forward to the review :)

robagar
23-05-2007, 05:44 PM
I finally got a look through the new ep last night with my 8" F6 dob :)

First thing noticed was that with the eyepiece inserted fully, it could not be brought to focus. I don't know if this is commonly the case with wide angle ep's (or 2" ep's?), but I guess I'll have to get an extender of some kind.

Once I had it focussed and with my eye jammed in to see the whole vista (not much eye relief), I had a good look at things, starting with the Jewel Box, Omega Centauri and Jupiter. Omega Cent looked like it was underwater through any ep, and there was too much tropical haze to see any dim DSOs.

Bad points

some field curvature and off-axis coma, giving a soft view away from the center with seagull shaped stars right at the edge.
ghost images of bright stars and planets. Dramatic lens flare effect looking at Jupiter.
Good points

the wide angle view is very nice.
vivid Jewel Box star colours
price - $125 I liked the sense of having peripheral vision. Even if things are not completely sharp they still add to the overall aesthetic effect. The coma is not noticeable if you are concentrating on the center of the view. In any case, looking though my old 26mm plössl now feels like a spotting scope.

Conclusion: a good eyepiece for open clusters and other extended (but not too bright) objects. One day I may save up enough for a Nagler to replace it, but until then I think I'll enjoy this one.

Finished the session with a hunt for Gliese 581 to say hi to the neighbours :)

The cloud has come back now :(

janoskiss
23-05-2007, 06:29 PM
Enjoy but don't think that Nagler is the next step. You should try a 13mm Stratus or Hyperion instead. Not a lot more expensive but much better EPs. Work very well in scopes like yours - no seagulls! :)

robagar
24-05-2007, 06:58 AM
Maybe, but I was after as wide a field as possible just to see what difference it made. Hyperion and Stratus ep's give 68°, vs 80° for the UW (and $90 cheaper, for the Hyperion at least) I'm sure that 12° makes all the difference ;)

allan gould
24-05-2007, 08:18 AM
I assume you are using these 80 degree eyepieces in a fast dob. They really dont perform all that well with these scopes. But put them in an f10 SCT and they are brilliant. I have the 30 and 15mm and they have blown most people away when they find out how little they cost for the type of view

robagar
24-05-2007, 09:07 AM
yes, fairly fast (F6). I was expecting a fair amount of distortion, so I'm not unhappy with this ep at all.