astronimica eyepieces any good?

[tyler_jrb]

Hey all, been looking at various eyepieces form my new scope(skywatcher skyliner 150p,1200mm 6"). I am wanting an eyepiece giving around 100-110x magnification so 11-12mm for some dso's and then with a barlow for planets at around 220x. So I want to go for around 40 pounds on a quite decent eyepiece a step up from the supplied ones that came with the scope. I have had a look at the meade 4000 series the 12.4mm they look good and are on my budget. I have also looked at the celestron omni 12mm which again sounds good and both have good reviews they will give me 100x and 200x with barlow again wondering if anyone has used them and how good they are. But then I looked at the astronomica 11mm and it also looks good. claiming things that I want in the eyepiece, (Ultra wide angle 80 degrees, high quality fully multicoated glass. Super sharp, high contrast & excellent aberration correction, extremely high resolution). Just wondering if anyone has heard how good they are or used them to reccomend me to them as I dont have a clue. All help appreciated.

11mm Ultra Wide Angle Eyepiece (1.25 inch fitting)

[John]

There is a review of that eyepiece here:

Zhitong 11mm 80° Wide Angle 1.25” Eyepiece - Review

I reckon it would work OK in your F/8 scope but the field edges will get very messy in a faster scope.

If you can get your whole wish list for £40 be sure to let everybody know

[brommas]

Your link is making my a/v go mad, showing as a" trojan-downloader.js.iframe.chf", kaspersky 2012, check link please, not prepared to overide a/v to take a look.

Thanks

[johninderby]

I had one of these. Actually surprisingly good with nice contrast and sharpness in an SCT or Mak. In a fast scope distortion became a real problem but if you stick to f/8 and over it should be OK.

BTW the 16mm version isn't too good and is best avoided.

John

[russ]

They work okay in slow scopes (F8 or slower). Eye relief is very tight and the field stop mushy. The 16mm version i think i saw somewhere say it was only a 70deg afov. The 11mm is by far the better of the two. I had the 11mm under the Burgess Optical name in a close out sale. I thought it worked okay in my SCT and Orion Optics 6" F8. Should be okay in your 150PL.

[Cornelius Varley]

From the Cloudy Nights Review:

Testing in daylight it was immediately obvious that there was noticeable chromatic aberration right on the edge of the expansive field of view. However, this only affected the outer 5% of the diameter of the field of view. The other noticeable feature was the very short eye relief. To get the full field of view visible, you have to place your eye right up against the eye guard. This is most definitely not an eyepiece for those who wear their glasses while observing.

Over the next two nights I tried the eyepiece out on several targets including the open cluster M39, the Ring Nebula M57, the doubles Epsilon Lyra and Eta Cassiopeia, the star Vega and on the Moon (not literally). Let me start off with my general impressions. I was pleasantly surprised by this eyepiece. Overall on-axis sharpness and contrast were good. At all times internal reflections were kept to manageable levels, and were not substantially worse than on my Meade 4000 series 9.7mm Plossl. The field of view appears to be a little less than advertised at about 76 degrees. Because of the short eye relief, one does have to move around a lot to see the whole field of view. Pin cushioning was noticeable, but not overly obtrusive. Not surprisingly, off–axis was performance not as good, but I must say it was a lot better than I had feared from such a low cost ultra-wide angle eyepiece. Fainter objects were sharp out to about 65% to 70% of the field of view. Beyond this a small amount of spherical aberration started to become apparent. Bright objects in the outer part of the field of view started to show definite “sea gulling” started to occur from about 75% out. From about 80% out from the centre, the spherical aberrations started to increase until at about 90% out, very bright stars were highly distorted. Chromatic aberration was only really noticeable when observing bright objects very close to the edge of the field of view. When viewing a relatively dim open cluster, there was no noticeable chromatic aberration. However, when viewing a 12 day old Moon there was noticeable chromatic aberration around the edge of the field of view, but not around the Moon. It is important at this stage to point out that these spherical and chromatic aberrations were only really apparent on bright objects, such a Vega. When viewing M39 (an open cluster) these aberrations were far less apparent and were acceptable right out to 95% of the field of view. Beyond this there was some elongation of star images, but at no point did it reach unacceptable levels.

By the way, this eyepiece is great for observing the Moon; especially when it is close to full. I found it particularly useful for tracing the path of ray systems right across the Moon’s near side and for scanning the lunar terminator. As expected, it was not as good for teasing out detail as my Meade 4000 series 9.7mm Plossl.

In summary, this is no Nagler, but for just $45 this is a remarkably good ultra-wide angle eyepiece and a good introduction to the joys of ultra-wide angle observing for those on a tight budget. Off-axis performance was remarkably good for faint objects right up to 95% of the field of view. The off-axis spherical and chromatic aberrations were only really a problem on very bright objects. I can see this eyepiece being particularly suited to observing smaller open clusters, extended faint fuzzies, and for scanning the lunar terminator. Remember, this test only relates to use on my slow (f13.6) ETX 90 and how well performance holds up on faster telescopes I cannot say. For me, this is a definite keeper (until I can afford a Nagler).

Peter