TS Optics SWA 100 Ultra Series

[Ags]

Simple question - are these "TS Optics SWA 100 Ultra Series" any good? I am attracted by the relatively low weight and the moderate length. I'd be using them in f6 scopes.

https://www.teleskop-express.de/shop/product_info.php/info/p7919_TS-Optics-SWA-100--Ultra-Series-10-mm-1-25--Xtreme-Wide-Angle-Eyepiece.html

[badhex]

Do we know who makes them? Might be possible to find other white labels with reviews? 

[Ags]

I have read some rumors the field is "only" around 90 degrees, but these were not reports from people who had looked through them. Also the TS write-up suggests these are an update of the original design, so maybe older reviews might not apply?

[badhex]

Maybe you've already seen this but this thread from a few years ago talks about them:

Our good friend @Louis D mentions that they are also available branded as 'Magellan' from Kokusai Kohki:

http://kokusai-kohki.com/products/magellan.html

 

[Louis D]

More than likely another branding of the Meade MWA line-up:

[Louis D]

2 minutes ago, badhex said:

Maybe you've already seen this but this thread from a few years ago talks about them:

Our good friend @Louis D mentions that they are also available branded as 'Magellan' from Kokusai Kohki:

http://kokusai-kohki.com/products/magellan.html

 

I had totally forgotten I'd posted that almost exactly 3 years ago.  Good catch!

 

[Louis D]

They're reviewed here in Omegon Panorama II livery:

[globular]

1 hour ago, Ags said:

the TS write-up suggests these are an update of the original design, so maybe older reviews might not apply?

The TS website has had the same write-up since 2017... as per the (wonderful) wayback machine archive:

https://web.archive.org/web/20170909195710/https://www.teleskop-express.de/shop/product_info.php/info/p7919_TS-Optics-SWA-100--Ultra-Series-10-mm-1-25--Xtreme-Wide-Angle-Eyepiece.html 

[Louis D]

2 hours ago, badhex said:

Do we know who makes them? Might be possible to find other white labels with reviews? 

I think we can rule out KUO (Kunming United Optical) that makes the well regarded APM/Lunt/Stellarvue/Myriad/WO/Astro-Tech/etc. XWA 100 degree eyepieces.  Why would they also sell a poor, non-competitive, false 100 degree line of eyepieces?

We can probably rule out JOC/Explore Scientific/Bresser since they also have a bonafide 100 degree line of eyepieces (ES-100).

That would leave Long Perng (I doubt it having never seen these on their website) and some others.  If I had to guess, it's the same company making the Celestron Luminos and its bretheren since both are flawed interpretations of other eyepiece lines (i.e., Ethos and Naglers) with overstated eye relief figures.  However, no one seems to know who is making the Luminos line, either.

[Louis D]

Here's my take on the 26mm Meade MWA that no other branding seems to have ordered:

It's flawed, but it kind of grows on you.  I'm keeping mine as a rather unique eyepiece that is no longer available.  It's sort of a 25mm (it's true focal length) Morpheus with barrel distortion and SAEP.  Until Baader markets a 2" Morpheus in that range, it will have to do.

[badhex]

Unsurprisingly S@N give a good review of the Omegon version, but then they give good reviews of everything so I'm not really sure how trustworthy it is.

So, apart from the TS specs, other versions (Magellan, Omegon) seem to match with the Meade 100° MWA. 

@Don Pensack also wrote on CN that the Omegons have exactly the same specs as the Meades: https://www.cloudynights.com/topic/654022-omegon-panorama-ii-meade-mwa/

If indeed this is the case then we can trust the reviews from the Meades. Ernest in Russia does a review of the 5mm, which he conditionally recommends for some use cases noting that the measured AFOV is more like 86°: https://astro--talks-ru.translate.goog/forum/viewtopic.php?f=32&t=4076&_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp&_x_tr_sch=http#p78487 

I've found his reviews to be pretty accurate to my own experiences, but obviously it's not a given that one passable FL means the rest will be also be okay. A bit of digging around elsewhere suggests that they are generally not that well thought of. Bit of a shame as I do quite like the look and shape of the TS/Magellan version. 

Oddly enough TS also does their own version of the well regarded APM 100° XWA series, but these are 80eur more expensive and pretty hefty in comparison. Perhaps it's currently just not possible to get reasonably priced, lightweight and well corrected 100° EPs - an astro version of "cheap, fast good: pick two". 

Edited July 22, 2022 by badhex

[Louis D]

If you scroll down to the bottom of the posting by Ernest, he tests the 26mm Meade MWA.  Above that, he mostly rags on my report as being methodologically flawed because I use comparative analysis against my other eyepieces to arrive at photographically derived central and edge focal lengths as well as AFOV.  He never even tries to put a value on the edge radial focal length.  I take all the claimed and measured values, run a best fit mathematical analysis on the data, come up with a coefficient, and apply it across the board.  With 70+ data points (eyepieces), the fit is pretty darn good.  For the 26mm Meade MWA, central focal length is 25.1mm while the edge radial FL is 21.2mm, so not much variation.  With my method, I can even measure/calculate the easy and full AFOVs that Ernest doesn't both to measure.  They are 79.4° and 83.3°, respectively.  Thus, you don't lose all that much AFOV due to SAEP by pulling back to 18mm of eye relief to avoid 95% of it.

Ernest goes on to nitpick that the eyepiece doesn't deliver 100° AFOV, but 83.6° (really close to my measurement) instead:

Claimed to be 100 degrees with an actual angular field of view of just 84 degrees! The audacity of Meade is amazing. Even the effective field of view (across the aperture) is only 90 degrees. That is, it is never a competitor to the 25 mm 100-degree from Explore Scientific.

However, he fails to grasp that it delivers the same TFOV as the 25mm ES-100 since both have a 41mm field stop, but with distortion opposite that of the ES-100.  Both have an eAFOV of 90° based on this common FS value, so both show the same TFOV.  They're basically a true competitor, just with opposite distortion.  Thus, the Meade is saying it delivers the same TFOV experience as its competitor's product in a deceptive way by claiming 100°.

Ernest even defends the 5mm and says below his review of this distortion difference yielding the same TFOV as others' 100° eyepieces:

'MWA in this sense are more "honest" eyepieces. And attacks from some observers are explained by a misunderstanding of basic optical concepts.'

And yet he falls into the same trap with the 26mm!  He needs to be consistent in how he applies his reasoning.

I also totally don't get his results at f/7:

In a telescope 1:7

Strong defocus at the edge of the field of view due to curvature

In the zone, a clearly visible halo of curvature slightly shifted to the side of the edge of the field of view

At 50% of the zone, the images of the stars are already noticeably "snotty"

All is well in the central area

At f/6 and f/6.7 in my field flattened refractors (ED and APO, respectively), I can't detect more than the tiniest defocus center to edge, and my eyes don't focus anymore to accommodate field curvature, so I would see it, but I don't.  Also, the stars are basically pinpoint to the edge.  It's barely worse than my 22mm Nagler T4 in this respect.  His words make it sound like it has an edge performance level similar to a 26mm Orion Q70, which it most certainly does not.  In fact, it is this lack of field curvature and lack of edge astigmatism that has made it grow on me despite its warts (strong SAEP and barrel distortion).

[Louis D]

9 hours ago, badhex said:

Perhaps it's currently just not possible to get reasonably priced, lightweight and well corrected 100° EPs - an astro version of "cheap, fast good: pick two".

Right.  Perhaps with exotic glass types and aspherical surfaces, one could achieve the latter two criteria while losing the first.

Of course, it they could sell millions of them like smart phones, the price would come down dramatically due to economies of scale.  If only 300 to 1000 iPhone 13's were made, as is the most likely case with the 26mm Meade MWA, they would be astronomically expensive (think hundreds of thousands to millions of dollars apiece to recoup R&D, wafer mask, and initial tooling expenses alone).  There just aren't enough amateur astronomers in the world to bring down the cost of exotic eyepiece production, so we'll likely never see them come to market.  Maybe some military will pay the tab for a short run of exotic eyepieces that we can then buy in 30 to 50 years time when the spares are surplussed due to obsolescence.

[badhex]

2 hours ago, Louis D said:

If you scroll down to the bottom of the posting by Ernest, he tests the 26mm Meade MWA.  Above that, he mostly rags on my report as being methodologically flawed because I use comparative analysis against my other eyepieces to arrive at photographically derived central and edge focal lengths as well as AFOV.  He never even tries to put a value on the edge radial focal length.  I take all the claimed and measured values, run a best fit mathematical analysis on the data, come up with a coefficient, and apply it across the board.  With 70+ data points (eyepieces), the fit is pretty darn good.  For the 26mm Meade MWA, central focal length is 25.1mm while the edge radial FL is 21.2mm, so not much variation.  With my method, I can even measure/calculate the easy and full AFOVs that Ernest doesn't both to measure.  They are 79.4° and 83.3°, respectively.  Thus, you don't lose all that much AFOV due to SAEP by pulling back to 18mm of eye relief to avoid 95% of it.

Ernest goes on to nitpick that the eyepiece doesn't deliver 100° AFOV, but 83.6° (really close to my measurement) instead:

Claimed to be 100 degrees with an actual angular field of view of just 84 degrees! The audacity of Meade is amazing. Even the effective field of view (across the aperture) is only 90 degrees. That is, it is never a competitor to the 25 mm 100-degree from Explore Scientific.

However, he fails to grasp that it delivers the same TFOV as the 25mm ES-100 since both have a 41mm field stop, but with distortion opposite that of the ES-100.  Both have an eAFOV of 90° based on this common FS value, so both show the same TFOV.  They're basically a true competitor, just with opposite distortion.  Thus, the Meade is saying it delivers the same TFOV experience as its competitor's product in a deceptive way by claiming 100°.

Ernest even defends the 5mm and says below his review of this distortion difference yielding the same TFOV as others' 100° eyepieces:

'MWA in this sense are more "honest" eyepieces. And attacks from some observers are explained by a misunderstanding of basic optical concepts.'

And yet he falls into the same trap with the 26mm!  He needs to be consistent in how he applies his reasoning.

I also totally don't get his results at f/7:

In a telescope 1:7

Strong defocus at the edge of the field of view due to curvature

In the zone, a clearly visible halo of curvature slightly shifted to the side of the edge of the field of view

At 50% of the zone, the images of the stars are already noticeably "snotty"

All is well in the central area

At f/6 and f/6.7 in my field flattened refractors (ED and APO, respectively), I can't detect more than the tiniest defocus center to edge, and my eyes don't focus anymore to accommodate field curvature, so I would see it, but I don't.  Also, the stars are basically pinpoint to the edge.  It's barely worse than my 22mm Nagler T4 in this respect.  His words make it sound like it has an edge performance level similar to a 26mm Orion Q70, which it most certainly does not.  In fact, it is this lack of field curvature and lack of edge astigmatism that has made it grow on me despite its warts (strong SAEP and barrel distortion).

It's a bit of a shame Ernest is quick to dismiss another's opinion, but honestly Louis, I wouldn't worry.

From my perspective I think it's probably a case of a combination of translation issues, testing methods, personal experience at the eyepiece itself, and lastly just a differences of opinion. Frankly I always look at a number of different sources for trusted opinions and weight my decisions accordingly. Ernest, yourself, Don, John and a number others on SGL are always the first places I look for tests, but at the end of the day no one individual will necessarily be 'correct'.

I highly appreciate the technical nature of Ernest's tests, but I also think they don't always really cover the true experience at the eyepiece. I love the ruler test that you do as well as your reports from time at the eyepiece. Don has a level of the expertise on the supplier/manufacture side that others may not. John is my goto for real world usage of eyepieces at every level of affordability. Yet other members will offer other opinions.

For me personally, all of these factors are really important and I'm sure that many others both more and less experienced than myself feel similarly 🙂

[Don Pensack]

13 hours ago, badhex said:

Oddly enough TS also does their own version of the well regarded APM 100° XWA series, but these are 80eur more expensive and pretty hefty in comparison. Perhaps it's currently just not possible to get reasonably priced, lightweight and well corrected 100° EPs - an astro version of "cheap, fast good: pick two". 

You don't regard the APM XWAs to be reasonably-priced?  Compare them to ES or TeleVue or Stellarvue.

And, they're lighter, per focal length, than the other 100° eyepieces.  And well-corrected.

If you're waiting for the £100 100° eyepiece, it'll never happen, but they are under €250.

Astrotech in the US is selling them at $250, though shipping to the UK might be steep.

Those prices are pretty cheap for high-end eyepieces.

[badhex]

24 minutes ago, Don Pensack said:

You don't regard the APM XWAs to be reasonably-priced?  Compare them to ES or TeleVue or Stellarvue.

And, they're lighter, per focal length, than the other 100° eyepieces.  And well-corrected.

If you're waiting for the £100 100° eyepiece, it'll never happen, but they are under €250.

Astrotech in the US is selling them at $250, though shipping to the UK might be steep.

Those prices are pretty cheap for high-end eyepieces.

Well, that's not exactly what I meant. I don't think they are unreasonably priced per se but nor are they cheap - and what I consider reasonable may be outside other's budgets.i have not seen the XWAs for sale for anything less than about €275 through European retailers which is a good sum more than the €200 for the SWA. 

Regarding weight, the original post by Ags mentioned specifically an interest in the light weight of the SWA series, and I wouldn't really say 750g or thereabouts for the XWAs counts as light really. 

[Louis D]

32 minutes ago, Don Pensack said:

If you're waiting for the £100 100° eyepiece, it'll never happen, but they are under €250.

Remember the Zhumell Z100 100° eyepieces in 9mm and 16mm focal lengths?  IIRC, they were closed out for around $100 each at the end of their stock run.  I'm not saying they were well corrected, but they were cheap for a bit.

[badhex]

Sorry @Ags I guess we went a bit off topic! However, I think in short if you're happy to accept the shortcomings of these EPs it might be worth trying to find one second hand? Perhaps the Meades might be more likely to be available as they seem to be more common? 

[Ags]

I think I will stick to  68° and 82°... I am not interested in a mediocre 88° eyepiece and the real 100° eyepieces are simply too heavy.

[badhex]

Agreed. All my main EPs except orthos are in the 66-76° range and I personally find that to be the sweet spot for me. Not to say I'll never look further afield though 🙂

[Don Pensack]

Not as heavy as claimed.

Actual gram scale weights:

APM	XWA HDC	3.5	525
APM	XWA HDC	4.8	492
APM	XWA HDC	7	425
APM	XWA HDC	9	468
APM	XWA HDC	13	461
APM	XWA HDC	20	678

 

The weights for the 3.5mm and 4.8mm include the 2" adapter.  For the others, add 50g for the adapter.  The 20mm is already 2".

[Louis D]

So most are very close to a pound.  That fits in nicely with Pentax XW and Delos weights.

[badhex]

On 22/07/2022 at 00:26, Louis D said:

I think we can rule out KUO (Kunming United Optical) that makes the well regarded APM/Lunt/Stellarvue/Myriad/WO/Astro-Tech/etc. XWA 100 degree eyepieces.  Why would they also sell a poor, non-competitive, false 100 degree line of eyepieces?

I know we put the original topic to bed here, but on the question about the designers: the shape of the EP plus the rubber grip pattern was really familiar to me but I couldn't figure out where I'd seen them before, until the APM Super Zoom thread had a bit of a revival:

Maybe not an exact match but pretty close in design aesthetic. 

In this thread, Marcus from APM confirms the super zoom is KUO made. 

https://www.cloudynights.com/topic/758189-new-apm-zoom-eyepiece-77mm-154mm-75°-constant-fov/

I'm not saying this is hard evidence but if it is actually KUO made, it does seem a bit strange to have some pseudo-100° EPs when we know they make actually decent true 100° EPs. 

Then again, I guess they could just be manufacturing to a price point set by TS and others. 

[Highburymark]

Ags - the APM XWAs are currently available from Astrograph in the UK for £215, which is excellent value. The 20mm is a bit pricier, but still less than a third of the Ethos 21 cost.
Like Badhex I’m usually happy with narrower eyepieces, but I did pick up the XWA 20mm last winter as my one 100 degree EP - fantastic for showcase DSOs, and I was surprised how light it is.

[Ags]

I have looked through an Ethos 21 a few times, but I forgot to be wowed 🤣 It was at a group viewing event so I just had a quick peek at things and moved aside. At most I can say it was easy to look through, which you can't always say about widefields. 

If I was in the UK, I would be very tempted! But I am just researching these eyepieces, not rushing to buy. I might get one around 2024!