Posts Made By: Rod Kaufman

There's a new cloudy nights review on tha antares ultrawides that have been on the market for a few years. I tried the link to discuss the article on CN but it didn't work for me so I thought I would provide comments in this forum.
I found the article to be thorough and unbiased. I also agree with the author that the antares 8.6mm ultrawide is the best of the lot with the 19mm unit being a close runner-up.
I've described the 8.6mm unit as a real "kicker" and the overall performance of it is quite good in my fast 16" f4.5 dob. I have not been bothered by the "kidney bean" effect that the CN author describes in his review. I've also used the 19mm antares ultrawide in a discovery 12.5" f-5 truss dob and while there is image degradation at the edge, the overall performance is quite good.
The author also comments on the purported similarity of these oculars with synta eyepieces but notes the quality control on these is evidently superior. He also notes the apparent addition of a barlow in the 8.6mm unit which I've noted in this forum in my previous posts on these oculars.
If you want a high performance ocular for modest cost that delivers a wide field of view in a dob, consider the 8.6 unit for tracking planets. Again, I have not noticed the kidney bean effect in this ocular and I am curious to know if others have seen it.
At any rate, check out the excellent review on cloudy nights!

That's the question we are waiting to know more about,ie on axis and off axis performance of the nagler31mm vs meade30mm. Or put another way, the pineapple versus the big kahuna...

I think the comments from Mike Hosea are on the mark. I have the 15 and 23mm 1.25 versions and both work well at slow f-ratios but can't correct for their own astigmatism at their edges in fast scopes. They should be ok at F-8 and above and they will do reasonably well with a focal reducer/corrector in a schmidt/cass but a paracorr won't help in a fast scope. The on-axis views are still very satisfying as they demonstrate typical ultima-style sharpness. I would expect the 2" versions to be of similar design and function.

You may also want to consider the antares ultra-wideview eyepieces available through scopestuff and other vendors. I am not sure if they are parfocal but they will do reasonably well in your scope although they will exhibit some degradation at the edges. The 8.6mm does fairly well in my hardin 10" F-5 dob. FYI: I just had my review of the hardin dob posted in the review section of the astromart.

One method suggested by Ed Ting is to aim your favorite eyepiece at a uniformly, moderatetly lit light source and slip a barlow over the end of the eyepiece as you look through the eyepiece. You may have to do this several times to get it to work but you will notice how the barlow dims the image a bit. Some barlows dim the image more than others or add some color to the image. In comparing my Orion apo shorty ultima clone to my 2" GSO barlow from Owl Services, I find a bit more dimming with the Orion barlow versus the 2" GSO barlow.
Your mileage may vary...

Starzona has a 1.5X piggy back barlow that threads onto 1.25" eyepieces. It appears to be ultra-low profile, like a filter, for about 70.00.
Seibert also sells a 1.5x and he's a AM sponsor.

The last thing I need is another eyepiece but as an avid eyepiece junkie...
GSO has produced a new 5mm 65 AFOV five element ocular. The price was right from Owl so I've ordered one today. If I receive it before my dark-sky outing next week, I will test it and report if it's ghostless/flareless or not. Perhaps I'll have a chance to compare it with Floyd Blue's 5.2mm pentax XL.
I see Owl also has a 2" 38mm monster for about $25.00 less than the competition and it appears to be similar to the Burgess eyepiece that did fairly well in some reviews I've read. Hmm...

I finally got the chance to test my celestron 2.3mm ED eyepiece on Mars at Pinos on 11-05. The seeing permitted it after midnight in my 16" F 4.5 dob.
In general, I don't recommend the eyepiece. While it has ample eye relief and a large eye lens and lacks lateral color, it also lacks contrast and was no match for a 4mm vixen eyepiece paired with a 2X barlow.
A sleeper of an eyepiece is the 2" 32mm astrola eyepiece that accompanied my 10" hardin dob. It's apparently a GSO derived unit with about 55 degrees AFOV with a marginal amount of coma around the edges. Nice eye relief, no blackouts, and it did very well on the Veil nebula with an 0111 filter in my 16". Decent contrast and, for what it is, it's a sweet eyepiece.
Conditions at Pinos were very good with minimal temperature drops to about 50 degrees with intermittent clouds throughout the night. I had the best view ever of m33 with a crystalline presentation in my dob as well as in my former 12.5" discovery truss dob. I used a 15 mm ultima wideangle (forerunner to the axiom) and the galaxy appeared to explode in the eyepiece. My ex 12.5 Discovery did very well with it, too.
Very little traffic at Pinos with about 20 amateurs with several large APO refractors and a new 20" starmaster at first light: very impressive!

Floyd,
Too bad you weren't at Pinos on Saturday. You could have tried it out under adverse conditions. Twenty-two degrees with wind. It blew my desert storm cover off my scope and I had to do search and rescue to find it's crumpled (but usable) remains in the morning.
However, it was clear and we had a blast using Jake's new 4" meade apo with a brand new 80mm vixen apo mounted on top of it. The wind didn't bother either one and the images on both were great. It was first light for another amateur's 6" tak apo, what a nice outfit.
The wind subsided about 4:00 am and the winter sky was awesome. It was definitely a refractor night as the shorter tube models held up well in the wind. I can't say enough good things about that 80mm vixen apo: from it's 100mm tube to its massive ultrasmooth 2" focuser and its great optics. What a package and its bargain priced at our favorite camera store in Woodland Hills. Hmm...

Chuck,
Your experiences with the 1rpd 30mm/BW optic variant parallel my own. I viewed through one last night at Pinos and the edge was fairly sharp in a moderate focal length meade 4" apo. The sky was clear and dark with very windy conditions which made viewing through dobs impossible but the 30mm eyepiece in combo with the 4" apo readily displayed nebulosity around the pleadies without a filter. The contrast on the 30mm eyepiece was quite good.
A 35 mm ultima might serve your purpose but it may be prone to blackouts.