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TS 28mm/Meade PWA 28mm 82° vs ES 30mm 82° ?

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21 replies to this topic

#1 vkhastro1

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Posted 18 June 2021 - 11:07 AM

I currently own the TS Optics 28mm 82° eyepiece.

It is a clone of the previous William Optics 28mm 82° UWAN and the current Meade 28mm PWA 82°

eyepieces.

It is excellent in my f/7 and longer APOs and f/5ish reflectors (best results with a TV Paracorr coma corrector).

 

I used to own the ES 30mm 82° several years ago, loved the views but not the weight.

I did not own the ES 30mm 82° at the same time as my current TS Optics 28mm 82°.

So I never did a “shootout” between them.

 

Am I missing anything optically by not having the ES 30mm 82°?

or

Should I just call it a day and forget about getting the ES 30mm ?

 



#2 Barlowbill

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Posted 18 June 2021 - 05:37 PM

I have been waiting six hours to read what the experts have to say.  I guess they took the day off.


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#3 CeleNoptic

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Posted 18 June 2021 - 05:59 PM

Ernest has compared them and didn't find any significant difference, especially in slower scopes.



#4 thecelloronin

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Posted 18 June 2021 - 06:31 PM

Ernest has compared them and didn't find any significant difference, especially in slower scopes.

But what about the insignificant differences?



#5 sixela

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Posted 18 June 2021 - 08:19 PM

Depends on what you’re after. There is less pincushion in the KUO.

Less lateral colour in the KUO (TS, UWAN) but more edge of field astigmatism (I now have a 31T5 and at f/5.1 the difference really is there).

On axis I prefer the TS to the ES30, but only with the newer TV-like top (I hated that UWAN 28mm eye dish with a vengeance).

Edited by sixela, 18 June 2021 - 08:21 PM.

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#6 Barlowbill

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Posted 18 June 2021 - 10:17 PM

There ya go



#7 CeleNoptic

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Posted 19 June 2021 - 03:00 AM

But what about the insignificant differences?

The link I provided in my previous post connects to the bench-test results by Ernest at F/4 and F/10. So, the insignificant (at F/6+, IMO) differences would be
 
- the 30mm ES82 provides slightly wider TFOV, sharper views at the edge of FOV due to less astigmatism (obvious at F/4), but more lateral color. Those data are matching well what posted by sixela above. 
IMO, all those differences, especially at F/6+, are just nuances grin.gif, that depend on the observer's scopes and preferences.  But YMMV.
 
There is an older review which included the 28mm UWAN and 30mm Meade 5K UWA  (tested on a 8" F/5 Newton) where the reviewer asked the similar question as the OP and concluded
 
Both eyepieces are not perfect to the edges, but give impressive views with huge fields of view. 80% of the field are excellent, on the last 20% some star deformation becomes visible. Due to the longer focal length of the Meade the true field of view is about 5% more than for the UWAN. Eye relief is comfortable for the UWAN, the Meade's eye relief is somewhat longer. No ghosting or reflections are visible, and again the amount of scattered light is low. Hard to say which one to prefer - a look on the price may help here.
 
IMO, the OP has answered his own question:
 

It is excellent in my f/7 and longer APOs and f/5ish reflectors (best results with a TV Paracorr coma corrector).


But the prices for a new 30mm ES82 are pretty close now to a used Terminagler...



#8 vkhastro1

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Posted 19 June 2021 - 04:48 AM

“But the prices for a new 30mm ES82 are pretty close now to a used Terminagler...”

 

The ES 30mm 82 degree just took a massive jump in price from $375 US up to $499 US ~ 33% increase. 
Just think that only several years ago the ES 30mm was retailing for $199 US !

 

If you think that’s crazy take a look at the ES 12mm and 17mm 92 degree eyepieces -

an increase from $549 US to $799 US ~ 46% increase

A new TV 31mm Nagler Type V retails for $665 US and as mentioned used ones are ~ $500 - $525 US range.

I think the asking price of used TV 31mm Naglers will increase as a result of the ES price increase on the 30mm 82degree eyepiece.

 

The TS 28mm looks to be a real “bargain” but needs to be imported from Germany (I did just that and TS had excellent service).

Hopefully no increase from them as a response to ES price increases.


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#9 thecelloronin

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Posted 19 June 2021 - 06:12 AM

I don’t understand how ES determines those price jumps. Are people really in a position to buy an ES92 at $800 in any significant number when they were selling slowly before? Have their costs really gone up that much, or is it a cash grab in the hopes of establishing a new higher price memory amidst all this inflation?

 

Feels real bad. A $250 hike is just greedy…

 

I hope TeleVue stays the course for no other reason than to make ES look entirely unattractive. Pay $700 for premium glass from a guy that helped put humanity on the moon, or spend the same amount on an imitator.


Edited by thecelloronin, 19 June 2021 - 06:16 AM.

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#10 Jon Isaacs

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Posted 19 June 2021 - 07:46 AM

Depends on what you’re after. There is less pincushion in the KUO.

Less lateral colour in the KUO (TS, UWAN) but more edge of field astigmatism (I now have a 31T5 and at f/5.1 the difference really is there).

On axis I prefer the TS to the ES30, but only with the newer TV-like top (I hated that UWAN 28mm eye dish with a vengeance).

 

:waytogo:

 

I had the 28 mm UWAN before I bought the 31 mm Nagler.  The twist up eyecup was so large in diameter that I could not look squarely through the eyepiece, I had to tilt my head, I never felt like I got a good view.  I tried disassembling it, I contacted William Optics.. it was not possible.

 

It seemed to me that no one involved in design and marketing were actual amateur astronomers, the fad was twist up eyecups so it had one even it made the eyepiece hard to use.

 

I'm glad someone finally addressed this ergonomic nightmare and I'm glad someone of Sixela's skill and knowledge has weighed in. He's been around a long time and one of the very few that I inherently trust.. 

 

Jon



#11 Miranda2525

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Posted 19 June 2021 - 08:41 AM

I currently own the TS Optics 28mm 82° eyepiece.

It is a clone of the previous William Optics 28mm 82° UWAN and the current Meade 28mm PWA 82°

eyepieces.

It is excellent in my f/7 and longer APOs and f/5ish reflectors (best results with a TV Paracorr coma corrector).

 

I used to own the ES 30mm 82° several years ago, loved the views but not the weight.

I did not own the ES 30mm 82° at the same time as my current TS Optics 28mm 82°.

So I never did a “shootout” between them.

 

Am I missing anything optically by not having the ES 30mm 82°?

or

Should I just call it a day and forget about getting the ES 30mm ?

I once owned the 30mm Explore Scientific 82 degree. I didn't find it very good. Stars flared a lot and because the top lens is recessed, eye relief is decreased. It was nothing special for me.

 

I also used to own a 28mm William Optics UWAN and found the lenses better than the 30mm ES 82. Only thing I did not like about the WO 28mm UWAN was the overly wide top.

 

I now own a 35mm Televue Panoptic and IMO, it's better than any of those and I also prefer it over the 31mm Nagler.

The 35mm Panoptic has everything I need in a WF eyepiece:

 

-Better weight handling

-Easier eye placement

-Longer eye relief, easy with glasses if I ever need them in the future

-Comes close to a 30mm when used with my GSO coma corrector


Edited by Miranda2525, 19 June 2021 - 08:50 AM.

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#12 CeleNoptic

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Posted 19 June 2021 - 05:03 PM

The TS 28mm looks to be a real “bargain” but needs to be imported from Germany (I did just that and TS had excellent service).
Hopefully no increase from them as a response to ES price increases.

 
Well, ~$200 the eyepiece plus ~$80 UPS shipping accross the pond, so it'll be $280. The 28mm Meade PWA at $303 could be an option, at least in the US, not sure about Canada though. Pricewise same as the previous ES82 cost (new).



#13 CeleNoptic

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Posted 19 June 2021 - 05:27 PM

I think the asking price of used TV 31mm Naglers will increase as a result of the ES price increase on the 30mm 82degree eyepiece.

 
I'm not sure there is a direct relationship. Yes, global inflation progressing so all prices will raise but not necessary that dramatical. ES is a Chinese company and their product prices spike could be just the result of the tariffs war.  If i'm not mistaken, TeleVue importing products from Taiwan and Japan so it's a different story. I suspect, that ES will be struggling with their new prices after pandemic is over and the stocks repelenished, e.g. in a year or so.



#14 Jon Isaacs

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Posted 19 June 2021 - 06:37 PM

 
I'm not sure there is a direct relationship. Yes, global inflation progressing so all prices will raise but not necessary that dramatical. ES is a Chinese company and their product prices spike could be just the result of the tariffs war.  If i'm not mistaken, TeleVue importing products from Taiwan and Japan so it's a different story. I suspect, that ES will be struggling with their new prices after pandemic is over and the stocks repelenished, e.g. in a year or so.

 

 

I think the idea is that the competition for a used 31mm Nagler is a new ES 30mm 82 degree.  

 

"I can't buy the used Nagler at $525 but I can see the ES 82 degree at $350."

 

Now that the ES is $500, the used 31mm Nagler would seem to be your best bet.  

 

But basically, I think ES has priced themselves out of the market.  They are too close to a new TeleVue 31mm Nagler.  The Nagler is just too much better, $150 and now you've got a new 31mm Nagler.  I'd be looking for that $150.. 

 

Eyepieces like the 30mm APM UFF, the Meade PWA 28 mm, they are now filling market niche of the 30mm ES.  

 

The 40mm ES 68 degree is $519, the 41mm Panoptic is $526.. I think very few would choose the ES 40mm over the 41mm Panoptic.  

 

Jon


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#15 Adam Long

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Posted 20 June 2021 - 06:50 AM

Anybody weighed the TS? I was happy to pay a little more for the reduced weight and better ergonomics of the Meade version. 

 

I read a lot of reviews before buying and there are a significant number of folk disappointed by the optics in the ES, whereas the UWAN was more or less universally praised for the optics (but not the ergonomics). This could be down to sample variation of course, and/or that there seem to be a lot more ES users out there.



#16 Jon Isaacs

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Posted 20 June 2021 - 07:56 AM

Anybody weighed the TS? I was happy to pay a little more for the reduced weight and better ergonomics of the Meade version. 

 

I read a lot of reviews before buying and there are a significant number of folk disappointed by the optics in the ES, whereas the UWAN was more or less universally praised for the optics (but not the ergonomics). This could be down to sample variation of course, and/or that there seem to be a lot more ES users out there.

 

There's a lot to consider.

 

- The UWAN is an older eyepiece so it had less competition. 

 

- Both these eyepieces were/are less costly alternatives to the 31 mm Nagler.

 

- I owned the UWAN for 4 or 5 years, I could never get around the ergonomics, I didn't use it much, never felt the views were that sharp but couldn't really get a good view because of the ergonomics.

 

- There's a great variation in the way people perceive the aberrations in wide field eyepieces, some seem to just expect them and expect them, happily unaware that the stars away from the center of the field are far from tight round dots.. others have high expectations and awareness.

 

The telescope used make a difference..

 

- I don't pay much attention to reviews, I pay close attention to observers I trust. When Don Pensack evaluates an eyepiece, I have at high confidence level. When Sixela evaluates an eyepiece, I trust it. These are knowledgeable, skilled observers with lots of experience.

 

https://www.cloudyni...3&qpid=11175743

 

Jon



#17 stevew

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Posted 22 June 2021 - 02:10 AM

I still love my ES82 eyepieces.

When I got them they were a bargain for the price i paid.

The quality is excellent . But at the new prices I'm sure there are options.

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#18 thecelloronin

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Posted 22 June 2021 - 07:05 AM

Why is the 14 the shortest?



#19 Jon Isaacs

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Posted 22 June 2021 - 07:51 AM

Why is the 14 the shortest?

 

The 1.25 inch type 6 Naglers are similar in this regard.. (That should be no surprise)

 

These eyepieces consist of two basic sections, a negative lens group in the barrel that is essentially an optimized Barlow and the positive magnifying group in the body.  These are "negative-positive" eyepieces, similar to a Barlow with an eyepiece.  

 

The eye relief comes from the longer focal length positive section, these are probably all very similar, based on the eye relief, the positive eyepiece is probably about 20mm. 

 

The focal length is determined by the negative lens.  The 14mm would have a 1.4x negative lens, the 4.7 would have 4.2x negative lens... similar to a Barlow, longer = greater magnification.

 

Jon



#20 thecelloronin

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Posted 22 June 2021 - 08:52 AM

What about the longer focal lengths than 14mm? Do they lack the Smyth/Barlow lens of the shorter focal lengths? Unless I’m mistaken, your post describes the right half of the U shape only.



#21 sixela

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Posted 22 June 2021 - 11:29 AM

They don't lack them, but it's indeed not a scaled design (if it were a scaled design, then the 14mm would be larger than the smaller focal length ones). Actually, it looks like the line from 14mm onwards to higher focal lengths is close to a scaled design, while the shorter ones look like a design that is not scaled (i.e. with a Smyth lens spaced progressively further away to decrease the combination's effective focal length.)

 

the reason for that is simple: the 14mm has more or less comfortable eye relief. If you were to simply scale the design down then the eyepieces would become less and less comfortable in shorter focal lengths since the eye relief would also scale down with focal length. If you slightly scale the design down and then increase the distance between the negative and positive groups, then you can get a shorter effective focal length eyepiece with the same eye relief (the price you pay for not scaling the design down is that you need bigger and wider lenses than if you had scaled it; the eyepiece is also longer but there is something as "short enough"). 

 

If you want to see a pure scaled design, here's the type 5 Nagler:

tele-vue-tele-vue-nagler-series-type-5.j

 

These do indeed get bigger and wider with increasing focal length.

 

You could make a 8mm T5 that was twice as short and twice as narrow as that 16T5, but it would have an eye relief of 5mm, and no one would find that comfortable for a 82° AFOV eyepiece (God knows how many people complain about the eye relief of the 16T5, even though I love it). 

Since the larger Meade 5000 UWA that later became the ES 82° were --ahem-- 'inspired' by the T5 Nagler (a range which goes from 16 to 31mm, with the 30mm a direct competitor to the Holy Handgrenade aka 31T5) you can see where they started to adopt a more or less roughly scaled design.


Edited by sixela, 22 June 2021 - 11:36 AM.

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#22 Jon Isaacs

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Posted 23 June 2021 - 12:09 AM

Just to add to Sixela's wonderful post:

 

The Smyth lens in the Type 5 Naglers doesn't have much of a Barlow effect. I have taken the barrel off both the 16mm and the 31mm Naglers and measured the field stop diameter.  The field stops are only a few percent larger than the published spec for the effective field stop diameter.  

 

Since the field stop lies at the focal plane of the rear section of the eyepiece, after the Symth lens but before the magnifying section, this means there is very little magnification in the Smyth section.  It is there to correct aberrations.

 

Ernest distinguished between these two types of designs but I can't quite remember the acronyms he used.  I think one was FLFFF or something Field Lens Far From Focus.  That would be the short focal length eyepieces with a barlow like negative group in the barrel.

 

Jon




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