Pentax XW 10mm vs ES82 8.8mm: Should I or shouldn't I?

[MetroiD]

I recently upgraded from an 8" to a 10" dob and have found the difference to be quite eye-popping, if you would forgive the pun... My DSO EPs are a 2" 24mm Meade 5k, a 1.25" 16mm Nirvana UWAN, as well as the 1.25" ES82 8.8mm which everyone seems to consider the best in ES' 82-degree range. I've been looking for a second hand 12.5mm Baader Morpheus for ages now since I'm admittedly loathe to splashing 200GBP on a new EP, but in the meantime an opportunity seems to have arisen for me to snatch a pristine second-hand Pentax XW 10mm at a reasonable price. It doesn't look as though I'll be to test it in the field prior to the purchase, so I keep going back and forth in wondering whether I should (or even actually need to) splash out on this eyepiece. While it would probably cost almost as much as a new 12.5mm Morpheus, it is said to be one of _the_ most legendary EPs for observational astronomy. If I do get it, it would certainly make the ES82 8.8mm surplus to requirements which would help finance the purchase - I can't help but wonder though if the Pentax does indeed provide that much of a step up from the ES82? Losing 12degrees of AFOV does seem like a bit of a compromise, especially considering that this EP's primary use would be DSOs, and besides I must say I've so far been quite happy with the ES' performance.

What would you guys recommend - should I stick to my guns or should I pull the trigger on the Pentax?

[Alan White]

The Pentax should be excellent, I had a 10 mm a while back, super eyepiece.
Worked well in my mix of scopes at the time, but sold as I has grass is greener eyes and regret selling it ever since.

 

[markse68]

if you don’t buy it, can I? 😉

[GordonD]

The great thing about such a well regarded and popular eyepiece is that you can try it, and if it doesn't suit you then should be able to sell it on easily with little or no loss - it's free! (kind of ...). And if you do prefer it, then the ES82 8.8mm (one of which I owned and thought very highly of) should also prove east to sell.

Gordon

[Timebandit]

 

The short Pentax XW set 3.5XW to the 10XW are excellent eyepiece's in my opinion.

Had my Pentax 10XW for numerous years , purchased second hand, the eyepiece optics are sharp like a Ortho, but great eye relief and good fov. Have never regretted purchasing this eyepiece. Use it in the reflectors at around f /4.7 and my refractor also.

A real "Keeper" in my opinion.

 

[Roger_Laureys]

Quote

 

I would go for a Delos eyepiece. They are  a bit sharper than the Pentax. I sold my XW 10 and never looked back

[John]

A few years back I was loaned a 10mm XW by First light Optics. I compared it with the Nagler T6 9mm that I had then and found the 10mm XW, although having a smaller field of view (of course) was a touch sharper, had less light scatter around bright objects and presented a "whiter" view of bright objects.

I loved the Nagler T6's so I was very interested to find something that was a touch better.

I now own a set of both Delos and XW's and use them one after the other during sessions. For me they are practically identical in performance. The Delos costs £87 more than the XW here in the UK.

 

 

[Sunshine]

I wouldn't give up my pentax eyepieces, they're fantastic bits of astro kit.

[Don Pensack]

7 hours ago, MetroiD said:

I recently upgraded from an 8" to a 10" dob and have found the difference to be quite eye-popping, if you would forgive the pun... My DSO EPs are a 2" 24mm Meade 5k, a 1.25" 16mm Nirvana UWAN, as well as the 1.25" ES82 8.8mm which everyone seems to consider the best in ES' 82-degree range. I've been looking for a second hand 12.5mm Baader Morpheus for ages now since I'm admittedly loathe to splashing 200GBP on a new EP, but in the meantime an opportunity seems to have arisen for me to snatch a pristine second-hand Pentax XW 10mm at a reasonable price. It doesn't look as though I'll be to test it in the field prior to the purchase, so I keep going back and forth in wondering whether I should (or even actually need to) splash out on this eyepiece. While it would probably cost almost as much as a new 12.5mm Morpheus, it is said to be one of _the_ most legendary EPs for observational astronomy. If I do get it, it would certainly make the ES82 8.8mm surplus to requirements which would help finance the purchase - I can't help but wonder though if the Pentax does indeed provide that much of a step up from the ES82? Losing 12degrees of AFOV does seem like a bit of a compromise, especially considering that this EP's primary use would be DSOs, and besides I must say I've so far been quite happy with the ES' performance.

What would you guys recommend - should I stick to my guns or should I pull the trigger on the Pentax?

the key things:

--you're not sure you want to give up the larger apparent field.

--you're concerned about the cost

--you're happy with the 8.8mm ES

So here is what I advise: skip the XW and keep the 8.8mm ES.  When you feel like upgrading to something inexpensive but perhaps a treat, try the APM XWA 100° 9mm.  No compromise in apparent field there, and about the same eye relief.

Or, really splurge for the TeleVue 8mm Ethos.  It would be a big step up in field size and optical quality.

[Louis D]

You could also try the 9mm Morpheus.  Try as I might, I can't find much to distinguish its performance from my 10mm Delos.  You'd also be giving up very little in apparent field of view.

[MetroiD]

Thanks for your responses guys! As I was expecting, the XW's are held in high esteem and it definitely seems like this would be a "safe" purchase.

15 hours ago, markse68 said:

if you don’t buy it, can I? 😉

Ah, just what I needed; a proper nudge in the direction of a purchase

In all honesty though, I'm now having second thoughts as to whether it wouldn't be more astute to have a long hard look at the Morpheus EPs, after all... Almost everyone seems to be very fond of them and I've read on more than one occasion how in terms of comfort and they beat 82-degree EPs without actually sacrificing any noticable TFOV. Ah, decisions, decisions. Well, at least I've got the 8.8mm to keep me warm until I've made up my mind.

There's still some likelihood that I might be able to test the Pentax side by side with my current ES82 - of course, I'll definitely report back on my findings once / if that happens.

[Stardaze]

I’m not sure where to go with the 9mm myself. Currently have the ES 6.7 and 11 (82) along with the ATP 13 and buying the 20mm version next month. I’ve read a few comments that the ATP 9 is bettered by the Morpheus and at that FOV I’m not certain that I need 100 degree? Got a month to suss it out. What’s your opinion @Don Pensack be interested?

PS. I do really like the ES 82s I have. 

[MetroiD]

1 hour ago, Stardaze said:

I’m not sure where to go with the 9mm myself. Currently have the ES 6.7 and 11 (82) along with the ATP 13 and buying the 20mm version next month. I’ve read a few comments that the ATP 9 is bettered by the Morpheus and at that FOV I’m not certain that I need 100 degree? Got a month to suss it out. What’s your opinion @Don Pensack be interested?

PS. I do really like the ES 82s I have. 

Is there such a significant difference between the APM HDC-XWA 13mm and the ES82 11mm so as to warrant holding on to both? By the way, in this particular conundrum I believe a lot of observers seem to point towards ES92, as long as you're willing to stick to 2" only - and those only come in 12mm and 17mm (so far) so the APM 20mm would complement them rather nicely. That would, however, still leave you with a choice to make in terms of <10mm EPs...

As for myself, for the time being, it seems as though my window of opportunity has closed. Seller seems to have vanished in thin air, vacation season and all - so I guess I'll be holding on to my ES82 8.8mm. The lingering sense of slight disappointment pretty much hints towards the answer to my original question.

[Stardaze]

14 minutes ago, MetroiD said:

Is there such a significant difference between the APM HDC-XWA 13mm and the ES82 11mm so as to warrant holding on to both? By the way, in this particular conundrum I believe a lot of observers seem to point towards ES92, as long as you're willing to stick to 2" only - and those only come in 12mm and 17mm (so far) so the APM 20mm would complement them rather nicely. That would, however, still leave you with a choice to make in terms of <10mm EPs...

As for myself, for the time being, it seems as though my window of opportunity has closed. Seller seems to have vanished in thin air, vacation season and all - so I guess I'll be holding on to my ES82 8.8mm. The lingering sense of slight disappointment pretty much hints towards the answer to my original question.

Probably not is the answer I think. I bought the ES 11 thinking that I'd complete the range but have since discovered the APM range. 13 down to 9 is surely the route. Part of me thinks that the mix of 20/13/9 in 2" is perfect in my dob but I do plan to add a 127 mak and for that, the 1.25" will be needed. I have a nirvana 16 so for the mak - 16/11/7 would be a nice little set 🤔

[Louis D]

2 hours ago, Stardaze said:

I do plan to add a 127 mak and for that, the 1.25" will be needed.

Get a Mak to SCT thread adapter, a 2" visual back, and a 2" diagonal and you won't have to duplicate expensive eyepieces on the 127mm Mak.

[mikeDnight]

I found the 10mm XW to be a terrific eyepiece for faint nebulae. It is very transparent and in my 100mm refractor, presented nebulosity enmeshing the Pleiades beautifully. The Flame nebula and IC434  with good dark adaption was a real highlight through the 10mm XW. It also barlows beautifully and makes a great lunar and planetary eyepiece that is very orthoscopic. 

[johninderby]

18 minutes ago, Louis D said:

Get a Mak to SCT thread adapter, a 2" visual back, and a 2" diagonal and you won't have to duplicate expensive eyepieces on the 127mm Mak.

The Skymax 127 now comes with a 2” diagonal in the US.

https://www.skywatcherusa.com/products/sky-watcher-skymax-127

Edited July 4, 2020 by johninderby

[MetroiD]

Just a bit of a "conclusion" to this thread: I didn't get the XW 10, after all. Instead, as soon as I'd moved on the ES 8.8mm, I added a Morpheus 9mm to my E/P case, as Louis D had suggested. The fact that I already had the Morph 17.5mm and the 12.5mm made it that much simpler As you can tell, I've grown quite fond of this E/P range so I'm very happy with how things turned out.