3 Big Eyepieces .......

[John]

Over the past few months I've been lucky enough (courtesy of First Light Optics) to borrow a Skywatcher Nirvana 28mm and a Pentax XW30mm to try alongside my Tele Vue Nagler 31mm. I've jotted down some notes on how the three compare for anybody that might be interested - posted as a PDF as they would make a rather lengthy post

3bigeps.pdf

[Doc]

Firstly thankyou John for taking the time and effort in doing this it's very much appreciated.

A very imformative comparison and one I read very intently. As you know I own the 28 Uwan and I must agree with everything you have said, the Uwan really does hold it's own against it's more expensive rivals.

I agree the ergonomics of the Uwan/Nirvana take a little getting used to but after a while you don't notice the face cup and it becomes second nature to position your face in a certain position.

Once again thanks and I'm sure many people will benefit from it.

[Darren B]

Thanks, a great review using two different, but commonly used type of telescopes. I have the 28mm Uwan and agree with what you say about it.

FYI, the William Optics Uwans, Skywatcher Nirvana's and the Orion Megaviews are all made by the same company in China Link.

[Andrew*]

What a super review, John. Thanks so much for that.

I have the 28mm UWAN and have found it an extremely capable performer even in the 16" f/4.5 dob.

Clearly each eyepiece has its own advantages and you've outlined that very well indeed.

Andrew

[Mark at Beaufort]

John

A very enjoyable read and I am sure that a number of SGL members will be buying the Nirvana EP as a result. I hope that Skywatcher increases the number of EPs in this range - I really would like a 20 or 22mm.

Mark

[AndyH]

John

A very enjoyable read and I am sure that a number of SGL members will be buying the Nirvana EP as a result. I hope that Skywatcher increases the number of EPs in this range - I really would like a 20 or 22mm.

Mark

I'd like a 10 or 12mm to fit tween the 7 and 16mm.

Nice report John.

Andy.

[John]

Thanks for the positive feedback folks - much appreciated

As the Nirvana's are clones of the William Optics UWAN's and the Orion (USA) Megaview's (as Darren B points out) I guess the decision on whether the range expands won't be down to Skywatcher. I know that William Optics have been ased the question numerous times since the UWAN's came out but so far no sign of more of them

I reckon the clever Chinese / Taiwanese manufacturers have 100 degree eyepieces in their sights now though ......

John

[Macavity]

Good stuff. I think I will ever be in the market for "something" of the ilk, but in all honesty am unlikely to invest (sic!) in Nagler or Pentax. Nice to see "activity" in this area - I sense I can still do a tad better than my (reasonable) Hype 31 Asp. Nirvana? I guess a "21mm Ethos" clone, would "do me" too.

[TheMightyKong]

I reckon the clever Chinese / Taiwanese manufacturers have 100 degree eyepieces in their sights now though ......

John

They're already selling them - witness the Explore Scientific 100deg eyepieces, and these:

Google Translate

Which are sold in the US under this label:

Zhumell Z100 16mm Eyepiece with 100 Degree Apparent Field of View - Telescope Eyepieces at Telescopes

More to follow I'm sure, especially given that I'm not sure how strongly patent law is enforced where these are probably made.

[arad85]

Nice review John

[AndyH]

Nice find Kong !!

Especially the Kokusai Kohki link. They sell to the UK..........mmmmmm.

Andy.

[TheMightyKong]

They are also being relabelled as TMB in the US and sold here:

The TMB 100 series

which probably means they'll be available sooner or later from SCSastro here in the UK in TMB form.

[albedo0.39]

Nice solid review John. As Doc knows, we had some amazing sights from the Nirvana at Salisbury Star Party just off the back of the Ethos 13mm and were amazed. You have caputred the essence of the EP well - big, crisp and well corrected. I think this will be the battleground in the future (if not already) and the WO UWAN / Nirvana offering is right up there.

Thanks for taking the time to develop the report

Steve

[TheMightyKong]

Nice find Kong !!

Especially the Kokusai Kohki link. They sell to the UK..........mmmmmm.

Andy.

Now available from France here:

Scopemania.eu

so no import taxes charges.

[Astro_Baby]

Thanks for doing that review John - it really helps shape my thinking and its good to have non-magazine reviews of things from real life users.

[russ]

Nice review John, very helpful indeed.

All i need is an eyepiece that performs like the 28mm Nirvana but only costs the same as a Rigel 32mm. Now that would be great.

Russ

[MarsG76]

Thanks for the review.

[25585]

Good review John. I own a 35mm Panoptic which perhaps was not made at the time of your test. 

How would that and other newer 30-somethings with WFOV compare to your original trio?

[John]

The ES 30mm 82 degree would have compared very well I think. The 35mm Panoptic has been around for quite a while but I've not used one - there are a few Tele Vue eyepieces that I've not used and thats one of them !

Perhaps I ought to repeat the test (I still have the Nagler 31) but with some of the latest ~30mm 2" eyepieces included ?

 

[Stu]

Would be interesting John. I was impressed with both the ES 20/100 and 30/82

[Piero]

I observed through the 30mm ES (82deg) and 35mm Pan with my F6 dobson (no coma corrector) last time I was in Italy. 

Optically, they were very close. Small differences were: 

- the background was slightly more grey in the 30mm ES;

- the last 5-8% of the 30mm ES showed some trace of astigmatism; 

- without spectacles the 30mm ES is more immersive and a bit more comfortable (somehow eye placement was easier - not that it was difficult with the 35mm Pan..). Said this I preferred the 35mm Panoptic because it allowed me to use my spectacles when finding targets (which I generally do with spectacles on);

- I felt that the 35mm Pan went slightly deeper than the 30mm ES. Also, stars were slightly smaller and depicted with more precision; 

- The FOV of the 30mm ES is larger. This was noticeable when I compared the two side by side, but it was not a massive difference. To see this difference one needs to stick his eye onto the eyepiece and tilt the eye towards the edge. Personally, I do not like to observe in this way, so for me, the difference in terms of FOV between the two eyepieces was not so relevant. 

 

Ergonomically, these two eyepieces are different instead. The 30mm ES is larger and heavier (almost 1/3 more). 

 

Both these two eyepieces will do a fine work though. In my opinion a potential buyer should consider: 

- the resulting exit pupil with his/her telescope(s); 

- whether s/he loves UWA eyepieces;

- whether s/he is fine with the weight;

- whether spectacles are required for observing.

[N3ptune]

I noticed the exact same thing you say in your very interesting paper with my own eyepieces:

I believe – the thing is, premium quality eyepieces let you see this coma whereas lower costs ones tend to mask it with the aberrations that the eyepieces them selves are prone to when used at short focal ratios.