294 replies to this topic

[droid]

My personal experience with these eyepieces.

 

This last 2 mights have been perfect, the clear sky chart for Conneaut was the best its been in months 

 

Thursday and Friday 

 

So....Thursday I set up the 80mm williams optics f6.9 and the Meade 102mm f8, both refractors, side by side.

 

Grabbed the ATs and a 20mm Meade UWA to fill the gapf5 between the 28mm and the 16mm 

 

Started with the 28mm , I saw very little difference in performance in either scope. Very sharp, inky black sky, nice sharp stars, it's definitely a keeper. 

 

The 16mm , a few have said its the weak link in these eyepieces,  I don't see that. I love the 16mm jet black sky sharp stars all the way across. I spent a lot of my time with this eyepiece,  mesmerized by the view.

 

The 13mm, also extremely good, more magnification, so you loose a bit of that wide open spaces feel, but thats normal nothing wrong with the eyepiece

 

The 10mm, also extremely good, showed m92 perfectly, only mag. .That started to show granulation in the cluster.

Very good moderate high power eyepiece. 

 

Friday night is even better than Thursday night,

 

all the above still applies, using a 120mm f5 refractor.

 

I viewed M13, M92 in Hercules, M56 and M57 both in Lyra, M27 in vulpecula, M71 was behind the tree.and last but not least, M29 in Cygnus.

 

All were gorgeous in all the eyepieces. 

 

This night I was switching between the 20mm and the 16mm most of the time.

 

So if your having any doubts about these eyepieces I hope this alleviates some of those worry.

 

Only down side is the gaps in mag. Nothing between the 28mm and the 16mm, or between the 7mm which is actually 8mm and 4mm.

 

Also, they 1.25 inch eyepieces need infocus,, my refractors used above, have enough, but just , use of a Barlow isn't possible., unless you switch to a 1.25 diagonal. Which I chose not to do. 

 

 

Edited by droid, 15 September 2023 - 10:28 PM.

[KWB]

Only down side is the gaps in mag. Nothing between the 28mm and the 16mm, or between the 7mm which is actually 8mm and 4mm.

I would say that would depend on what telescope one is using and what you what as to a magnification range. For me there is no downside as to this gap from 28mm to 16mm, when used with my 80mm F/7 refractor, i.e, the 28mm eyepiece provides a a little over a 4 degree TFOV and a 4mm exit pupil at 20X. The 16mm has a 2.34 TFOV , a 2.29mm exit pupil at 35 X. I really don't need another focal length eyepiece in between these two. As always, YMMV.

 

The same scenario works out using my 102mm F/7 - 28mm/26X jumping to 16mm/44X. One the other end I use a 2X barlow with my 10mm to get to 5mm to plug that gap.

 

Bottom lime, I too am pleased with the performance of what I consider bargain priced eyepieces.

[scout]

I agree about the AT UWAs being great eyepieces. I have all five of the 1.25" UWAs and love them all. Sharp, contrasty and comfortable (for non-glasses wearers). Amazing that they're only $99 each. I'm getting the 2" 28mm UWA ($200) when it comes back in stock.

 

I keep reading posts saying, mainly about the 16mm, "...but they're not quite as sharp in the outer field as Naglers."

Well no kidding, they cost less than a third of the price of a Nagler. Of course a Mustang eyepiece isn't as perfect as a Ferrari eyepiece.

 

You want perfection in this hobby, you pay for it. If the UWAs had the same expensive coatings and optical perfection of a Nagler, they wouldn't be $99. But for their price, and compared to other similar, non-super-premium eyepieces, the UWA line is outstanding and an incredible bargain. 

[Jon Isaacs]

 

 

I keep reading posts saying, mainly about the 16mm, "...but they're not quite as sharp in the outer field as Naglers."

Well no kidding, they cost less than a third of the price of a Nagler. Of course a Mustang eyepiece isn't as perfect as a Ferrari eyepiece.

 

The 16 mm is more than "not quite as sharp" as the 16 mm T5 Nagler, the off-axis issues are quite apparent. I've used this eyepiece extensively

 

The others are better in this regard. 

 

When one is evaluating an eyepiece, the "but it only costs $100" comes at the end after the discussion of the performance and aberrations is finished.

 

I have the entire set of UWAs as well as the 31 mm Nagler the 16 mm and all the T-6s except the 2.5 mm. The UWA eyepieces are very capable but do not offer that perfection that the Naglers offer.

 

Jon

[droid]

I never compared the 2, I could I guess , assuming the 16 is actually 16, I do have the 16mm T2...I was just giving my impressions of the 4 I have.

 

I actually liked the 16mm , no it isn't perfect, didn't think it would be,  but I was happily surprised. It was as good as it was. I did keep swapping back and forth with the Meade comparing the views.

 

To my eye it was quite good, and worth every bit of the 99 dollars it cost.

 

Now you have me curious, the 16mm T2 vs the 16mm AT....hmmm

[SeattleScott]

Remember Jon’s scopes mostly operate around F5 so the 16 AT will do much better in your Meade refractor. Still a worthwhile comparison, just understand that some have a different perspective of the eyepiece, based on the F ratio of their scopes, and the other eyepieces they use.

Another issue. Jon uses large aperture scopes. If you really want to reveal the flaws of an eyepiece, put a brighter star near the field stop. In Jon’s scopes, they pull in enough light that even field stars can be somewhat bright. Or the NP101, same aperture as your Meade, but F5.4 so stuff will be much brighter (plus the edge correction issues dealing with that steep light cone). By comparison dim field stars will generally be pretty dim in your small, relatively slow refractors. So it hides the eyepiece imperfections much better. If you put a brighter star, doesn’t need to be Vega, just any reasonably bright star, near the edge of the field, you will see why some people aren’t crazy about the eyepiece. As long as you don’t use it on something like Pleiades that would fill the whole view with bright stars, one can largely ignore the imperfections of the eyepiece in your scopes. But the imperfections are there. You are just choosing not to highlight them. Which is fair.

Double Cluster would be a great target for that eyepiece in your scopes. There are some brighter stars and it is spread out enough that it could start highlighting the imperfections. It would be interesting to see what you think of the eyepiece used on Double Cluster in the Meade, where it should frame it nicely.

The same magnification isn’t required to test for edge correction. Certainly compare it to the 16T2, but you can also compare it to the rest of the series just by taking a bright star and seeing how pinpoint it stays as it approaches the field stop. They say the 16 is the worst, the 13 is better and then the rest are quite good. You could look to confirm those findings. Ultimately most eyepieces will do great in the center 50%. If you frame targets in the center 50% and just use the outer 50% as generous framing, you can be happy with most any eyepiece. But some like to frame targets with 70-80% of the view. Now abberations in the zone become more of an issue. Or maybe they look at galaxy groups where they are spread out around the view rather than just in the center. Some will place the target near one edge of the view and study it as it moves across the view while others just center the target, look for a few seconds and move on. There is a reason why some can’t imagine not using a coma corrector at F5 while others put hyperwides in their F5 Dobs without a coma corrector and are perfectly happy. It just depends on how they use the scope. Is the outer view being used to view the target, or is it just there for generous framing? Consequently there can be conflicting reports on eyepieces or even the necessity of coma corrector just based on how one views targets and what objects they view.

Edited by SeattleScott, 16 September 2023 - 10:03 AM.

[droid]

Ohhh I agree, don't misunderstand me, I agree with Jon 99 percent of the time. Jon and I have been friends for a while.  Jon is my go to guy when my limited brain power fails me, lol.

 

I have a 12 inch f4.9 dob, but am still unable to move it, I also have a 6 inch f8 refractor I'm currently unable to use.

 

The dob for sure would be a better test.

 

And actually Jon does own a long focus, kinda, achromat, a 120 f???8 I could be wrong on the focal length.

[tony_spina]

The 16 mm is more than "not quite as sharp" as the 16 mm T5 Nagler, the off-axis issues are quite apparent. I've used this eyepiece extensively

 

The others are better in this regard. 

 

When one is evaluating an eyepiece, the "but it only costs $100" comes at the end after the discussion of the performance and aberrations is finished.

 

I have the entire set of UWAs as well as the 31 mm Nagler the 16 mm and all the T-6s except the 2.5 mm. The UWA eyepieces are very capable but do not offer that perfection that the Naglers offer.

 

Jon

Jon how would you rank the 1.25" UWAs from worst to best based on your observations 

[balcon3]

The 16 mm is more than "not quite as sharp" as the 16 mm T5 Nagler, the off-axis issues are quite apparent. I've used this eyepiece extensively

 

The others are better in this regard. 

 

When one is evaluating an eyepiece, the "but it only costs $100" comes at the end after the discussion of the performance and aberrations is finished.

 

I have the entire set of UWAs as well as the 31 mm Nagler the 16 mm and all the T-6s except the 2.5 mm. The UWA eyepieces are very capable but do not offer that perfection that the Naglers offer.

 

Jon

Do you think that the differences would be noticeable in a 6 inch f/8 reflector? I am thinking about obtaining eyepieces with wider FOV than my Baader Classic Orthos in the 6-20mm range.

[SeattleScott]

The differences would still be noticeable at F8, they would just be less noticeable than at F5. The 16mm in particular has enough aberrations that it won't be perfect across the field at F8. Now if you don't ever put a bright star out near the edge of the field, maybe you won't care. If you don't ever put targets at one edge of the field and study them as they drift across the field, maybe you won't care. So it really is just a matter of how you use they eyepiece. If you use the ultrawide AFOV just for framing targets, you may be perfectly content with it. Or maybe you use the outer portion enough to notice it isn't perfect, but not enough to justify buying a Nagler/Morpheus/whatever instead. If you put a bright star at the edge of the field, you will be able to see a difference between the 16mm and the 4-10mm ones. But do you care, are you sensitive enough to edge distortion for it to matter enough to buy a $300 eyepiece instead? You would just have to try it and see. It's not like it is going to be a terrible eyepiece at F8. Droid is happy with it at F8. Would you be happy with it? No way to tell. Ernest's bench tests at F10, more forgiving than F8, suggest a spot size at edge of field of 20 for the 16mm and 8 for the 7mm. So at F8 that might be more like 25 versus 10. So the stars at the edge will be about 2.5 times the size of stars at the edge of the better corrected eyepieces. Now 10 is right about the threshold where stars still look more or less pinpoint to the human eye. So the 7 would basically look sharp across the field, but the 16 would show stars about 2.5x pinpoint at the edge, roughly speaking. Certainly not perfect, and certainly not terrible. Would it bother you personally? No way to know without trying.

 

I think the real takeaway here is that the 4, 7, 10 and 28 in particular represent a tremendous value as they are pretty well corrected across the field, even at F5, for a budget price. The 16 is not well corrected. It isn't a steal like the others. It could still represent a reasonable value to a user who has a slower scope and isn't fussy about edge performance. It just isn't the value proposition that the other focal lengths are.

[balcon3]

The differences would still be noticeable at F8, they would just be less noticeable than at F5. The 16mm in particular has enough aberrations that it won't be perfect across the field at F8. Now if you don't ever put a bright star out near the edge of the field, maybe you won't care. If you don't ever put targets at one edge of the field and study them as they drift across the field, maybe you won't care. So it really is just a matter of how you use they eyepiece. If you use the ultrawide AFOV just for framing targets, you may be perfectly content with it. Or maybe you use the outer portion enough to notice it isn't perfect, but not enough to justify buying a Nagler/Morpheus/whatever instead. If you put a bright star at the edge of the field, you will be able to see a difference between the 16mm and the 4-10mm ones. But do you care, are you sensitive enough to edge distortion for it to matter enough to buy a $300 eyepiece instead? You would just have to try it and see. It's not like it is going to be a terrible eyepiece at F8. Droid is happy with it at F8. Would you be happy with it? No way to tell. Ernest's bench tests at F10, more forgiving than F8, suggest a spot size at edge of field of 20 for the 16mm and 8 for the 7mm. So at F8 that might be more like 25 versus 10. So the stars at the edge will be about 2.5 times the size of stars at the edge of the better corrected eyepieces. Now 10 is right about the threshold where stars still look more or less pinpoint to the human eye. So the 7 would basically look sharp across the field, but the 16 would show stars about 2.5x pinpoint at the edge, roughly speaking. Certainly not perfect, and certainly not terrible. Would it bother you personally? No way to know without trying.

 

I think the real takeaway here is that the 4, 7, 10 and 28 in particular represent a tremendous value as they are pretty well corrected across the field, even at F5, for a budget price. The 16 is not well corrected. It isn't a steal like the others. It could still represent a reasonable value to a user who has a slower scope and isn't fussy about edge performance. It just isn't the value proposition that the other focal lengths are.

Thanks very much for your reply. It is very helpful. How can I get access to the results of these "Ernest's bench tests" that you mention?

Edited by balcon3, 16 September 2023 - 12:29 PM.

[Jon Isaacs]

 

 

 

I actually liked the 16mm , no it isn't perfect, didn't think it would be, but I was happily surprised. It was as good as it was. I did keep swapping back and forth with the Meade comparing the views.

 

I like the 16 mm UWA too. It's got some issues near the edge but I like the presentation and experience, it has that Nagler feel even if it's not so perfect.  

 

The 4 mm UWA is not as crisp and sharp as the 3.5 mm Nagler, I lose something there.  Overall, the biggest issue is that gap between the 8mm (7 mm) and the 4 mm but that's easily filled by Barlowing the 13 mm and 10 mm.

 

I think that for planetary/double star the UWAs give up a little, for deep sky they don't give up much at all.

 

I've got one more night in the high desert before I need to go back to San Diego for family stuff. I've been using the Ethos XWAs, I think I'll give the UWAs a go tonight..

 

Jon

[Starman1]

Thanks very much for your reply. It is very helpful. How can I get access to the results of these "Ernest's bench tests" that you mention?

http://astro-talks.r...2&t=1483#p41976

and go way down the page to the 2nd list, which has more eyepieces and additional details.

[EsaT]

I'm getting the 2" 28mm UWA ($200) when it comes back in stock.

Unless wanting matching brands, there's Stellarvue branded version of it.
https://www.eyepiece..._p/20101028.htm

 

I have it under Tecnosky brand of same name Italian shop.

[scout]

Unless wanting matching brands, there's Stellarvue branded version of it.
https://www.eyepiece..._p/20101028.htm

 

I have it under Tecnosky brand of same name Italian shop.

I'm holding out for the AT version to complete my set, (as a lifelong baseball card collector I guess I have a set building mentality), but thanks for the link. 

[Jon Isaacs]

Jon how would you rank the 1.25" UWAs from worst to best based on your observations 

 

Do you think that the differences would be noticeable in a 6 inch f/8 reflector? I am thinking about obtaining eyepieces with wider FOV than my Baader Classic Orthos in the 6-20mm range.

 

As I said, I like them all. The 16 mm has the edge issues but I still like it and enjoy the views. Ranks in order best to worse:

 

28 mm

7 mm and 10 mm

13 mm and 4 mm

16 mm

 

Some eyepieces have edge issues that are distracting. I find the 16 mm UWA enjoyable. It doesn't bother me. The 16 mm T-5 Nagler is stunningly sharp, pretty short on eye relief but a very special eyepiece. It's tough to compete against.

 

I think they'd be very good in a 6 inch F/8. Buy either the 7 mm (actually 8 mm) or the 10 mm and see what you think.

 

Jon

Edited by Jon Isaacs, 16 September 2023 - 05:18 PM.

[droid]

Ok everyone still reading, lol

 

We had a half a night, it clouded up after 1am, as I mentioned I did a side by side with the 16mmT2 vs the 16mm AT.

 

As many of you might guessed , the T2 won, but it wasn't a clean kill. The main difference was the edge of field correction.

And tweaking the focuser a bit, you extend the fov. To 85 percent and it didn't get really bad by  my unmeasured, guess of 90 percent.

 

That's not bad for a 99 dollar eyepiece,  the stars were a bit tighter and sharper in the T2, but not bad in any sense in the AT.

 

I still love the 16mm AT uwa. Lol

 

Note: my 16mm is the type 2, I have no experience with any of the type 4s,5s, or 6s....so if your using newer types your results may be better.

Edited by droid, 17 September 2023 - 02:16 PM.

[SeattleScott]

So if you balance the field curvature just right you can get a usable view out to around 85%, seems reasonable at F8. Slow scopes have their advantages.

The AT could have an advantage of delivering slightly brighter views due to more modern, higher transmission coatings.

Edited by SeattleScott, 17 September 2023 - 05:45 PM.

[Jon Isaacs]

Ok everyone still reading, lol

 

We had a half a night, it clouded up after 1am, as I mentioned I did a side by side with the 16mmT2 vs the 16mm AT.

 

As many of you might guessed , the T2 won, but it wasn't a clean kill. The main difference was the edge of field correction.

And tweaking the focuser a bit, you extend the fov. To 85 percent and it didn't get really bad by  my unmeasured, guess of 90 percent.

 

That's not bad for a 99 dollar eyepiece,  the stars were a bit tighter and sharper in the T2, but not bad in any sense in the AT.

 

I still love the 16mm AT uwa. Lol

 

Note: my 16mm is the type 2, I have no experience with any of the type 4s,5s, or 6s....so if your using newer types your results may be better.

 

Saturday night, I used my set of UWAs. The skies were dark (21.15 -31.35 mpsas) and clear. I was using the 16 inch F/4.4 with the Paracorr 2, that's F/5.06.

 

The 16 mm UWA performed admirably. It was not quite perfectly sharp at the field stop but it was difficult to see, it required inspection by direct vision. 

 

The field curvature in the scope at the edge of the 16 mm UWA weighs is less than the depth of focus at F/4..4, the telescope's field is flat.

 

Andy's scopes are slower but they have curved focal planes.  Field curvature of the scope plus some off-axis astigmatism is additive..

 

Jon

[RCLARK28]

Saturday night, I used my set of UWAs. The skies were dark (21.15 -31.35 mpsas) and clear. I was using the 16 inch F/4.4 with the Paracorr 2, that's F/5.06.

 

The 16 mm UWA performed admirably. It was not quite perfectly sharp at the field stop but it was difficult to see, it required inspection by direct vision. 

 

The field curvature in the scope at the edge of the 16 mm UWA weighs is less than the depth of focus at F/4..4, the telescope's field is flat.

 

Andy's scopes are slower but they have curved focal planes.  Field curvature of the scope plus some off-axis astigmatism is additive..

 

Jon

I really appreciate the data and feedback here from all members of this forum.

From my standpoint of being an older/new viewer these AT-UWA's have really appended a new challenge for me and have been a good purchase for me. I love the views with our older DOB and my two G-n-G scopes. I have the 4mm, 13mm & 16mm with the 10mm on the way. They will give me plenty of time until I can save and or purchase better EP's if needed. My goal is to use what I have and determine where to proceed. These AT-UWA's are good for me even with limited good seeing conditions. I plan on putting these in my rotation and making an effort to learn what my hardware will do. My first impressions are good, and I can't wait to test them further. They are a good solid purchase if you are just starting out or on a budget. These are performers for me.

Clear skies to all!

[KWB]

 They are a good solid purchase if you are just starting out or on a budget. These are performers for me.

Clear skies to all!

 

 

I would agree. They are 1.25 inch budgetary eyepieces IMO and for no more that what they cost. the overall performance is acceptable in my telescopes. These aren't perfectly corrected eyepieces in faster telescopes but they will do what I ask to have enjoyable experience at night.

 

My personal favorite is the 10mm UWA. Axial performance in my 80mm F/7 is terrific and is a well corrected eyepiece for off-axis astigmatism in the same telescope. This particular eyepiece is the closest to what I consider T6 Nagler performance in this telescope. My 9mm T6 Nagler is the closest focal length for a crude comparison and while there is no doubt that the TV eyepiece is a better overall performer IMO, that overall difference isn't highly significant. Long story short, the 10mm UWA is a suitable substitute for my purposes and if it was the only eyepiece I had in this focal length range I wouldn't look back.

 

Enjoy the eyepiece, my friend. 

[eric_zeiner]

I've had my set of AT UWA'S about six months now and I really enjoy them.  I have been using them in all of my AT scopes and they do a wonderful job.  It turns out that the 7mm has become my favorite.  In all honesty though, each one in the series has it's own strengths and weaknesses, but for a hundred bucks, I am quite pleased.

[Astroyesmer]

One thing to note about this series of eyepiece, 28mm aside, they are also fantastic to use with a binoviewer!

[dregan]

I have the 13mm and the 16mm and I feel as though they are very good. I use them for binoviewing. The eyepieces are sharp and the contrast is very good.

[eric_zeiner]

I have the 13mm and the 16mm and I feel as though they are very good. I use them for binoviewing. The eyepieces are sharp and the contrast is very good.

Yes, I totally agree with the contrast these EP's show.  Very nice.