eyepice for deepsky

[pleiades]

Hi, I am wonder what is the best or very good eyepiece for deepsky.

I will use it with a 14". I have seen so many and it's a difficult choice.

[russ]

A Televue Ethos would probably class as the best deepsky eyepiece for a 14" dob. With an extremely well corrected 100deg apparent field of view, it's just about perfect. The decision will be what size to go for?

[John]

I agree with Russ - the Ethos is superb. I find the 13mm extremely useful with my 10" F/4.8 newtonian but with a 14" you might find the 17mm a more versatile choice.

[pleiades]

Any opinion about Nagler T4 17mm or 12mm with 82 apparent field?

It's not 100 but...

Pentax?

[John]

Any opinion about Nagler T4 17mm or 12mm with 82 apparent field?

It's not 100 but...

Pentax?

All superb as well - you can't go wrong with those brands

The Pentax XW 14mm is a 1.25" format with a 70 degree field. The 12mm and 17mm Naglers are from the Type 4 range which have more eye relief than other Nagler types. The 17mm has a reputation for being a peach

At a lower price but still very nice would be a William Optics UWAN 16mm - again a 1.25" format eyepiece but one that offers an 82 degree FoV and 95% of the performance of Naglers.

[pleiades]

I will take a look at William Optics UWAN 16mm also.

Thank you John

[michael.h.f.wilkinson]

I can vouch for the Nagler 22 T4: a really superb EP, cannot find fault with it. I use it very often for smaller DSOs (but then my scope is F/10). For larger DSOs I opt for the 40mm Paragon, but that would give a 9mm+ exit pupil on most big Dobs. I like the fact that I can see the whole 82 deg FOV whilst wearing my glasses.

[pleiades]

I own a 22T4. It's superb view. But for deep sky... I don't know. On a 14" maybe is is the limit. Any way I thing 22mm is not for very deepsky observing.

[michael.h.f.wilkinson]

I own a 22T4. It's superb view. But for deep sky... I don't know. On a 14" maybe is is the limit. Any way I thing 22mm is not for very deepsky observing.

why not? If your scope is a F4.5, i.e 1600mm focal length, the magnification is 72x with a true FOV of over 1 degree, exit pupil is 4.9mm, i.e. just fine. Perfectly suitable for the larger DSOs. You might prefer a bit more magnification from the 17T4 or 12mmT4.

[pleiades]

Exactly Michael! I thing 17mm and for sure 12mm will be the best. For 22mm I am not so sure, but you have right at your calculations. I have to see...

As I understand now, my question in this thread is more for 8-17mm eyepieces.

[John]

All eyepieces are suitable for deep sky viewing - there are no "right and wrong" types in my opinion. Some times a very low power, wide field is needed and sometimes more power is the right approach. It depends on what you are viewing and the observing conditions.

I find 13mm is a focal length that gets used lots but I would not be without my 31, 20, 8 and 6mm's either - I've used them all for deep sky viewing at one time or another.

[russ]

Exactly Michael! I thing 17mm and for sure 12mm will be the best. For 22mm I am not so sure, but you have right at your calculations. I have to see...

As I understand now, my question in this thread is more for 8-17mm eyepieces.

I sort of know where you are coming from. For some reason i bypass the eyepieces in the 20-25mm range and dive straight in for the 17mm or possibly the 12.5mm. It's one of the reasons i sold my 20mm Meade SWA. It just never got used. And replaced with some very cheap alternatives.

But as John says, it's handy to have all sizes there because there's no right or wrong choice. But 12-16mm seems to be the sweet spot for a proper workhorse DSO eyepiece and probably the reason TeleVue released the 13mm Ethos first.....just such a good size in most scopes.

[michael.h.f.wilkinson]

I sort of know where you are coming from. For some reason i bypass the eyepieces in the 20-25mm range and dive straight in for the 17mm or possibly the 12.5mm. It's one of the reasons i sold my 20mm Meade SWA. It just never got used. And replaced with some very cheap alternatives.

But as John says, it's handy to have all sizes there because there's no right or wrong choice. But 12-16mm seems to be the sweet spot for a proper workhorse DSO eyepiece and probably the reason TeleVue released the 13mm Ethos first.....just such a good size in most scopes.

For me (using an F/10 scope) of course the 22mm plays the role of the 11 or 13mm in an F/5 scope. It does get used a lot. However, I still often use my 40mm (closer to the 22 in a dob) for wider DSOs and simply to find them. In my last hunt for 8 new DSOs I almost always found them more easily in the 40mm, and once found grabbed the 22mm.

[pleiades]

But 12-16mm seems to be the sweet spot for a proper workhorse DSO eyepiece and probably the reason TeleVue released the 13mm Ethos first.....just such a good size in most scopes.

Yes. And you have right to propose Ethos first. I also will see William Optics UWAN line John propose. At the end T4 is something reliable

[pleiades]

For me (using an F/10 scope) of course the 22mm plays the role of the 11 or 13mm in an F/5 scope. It does get used a lot. However, I still often use my 40mm (closer to the 22 in a dob) for wider DSOs and simply to find them. In my last hunt for 8 new DSOs I almost always found them more easily in the 40mm, and once found grabbed the 22mm.

Michael at your F/10 scope 40mm is the lower power eyepiece you have?

[russ]

For me (using an F/10 scope) of course the 22mm plays the role of the 11 or 13mm in an F/5 scope. It does get used a lot. However, I still often use my 40mm (closer to the 22 in a dob) for wider DSOs and simply to find them. In my last hunt for 8 new DSOs I almost always found them more easily in the 40mm, and once found grabbed the 22mm.

Wouldn't be without a low power eyepiece. I just need to get another, or at least keep nagging Keiran to sell back the Meade 5K 34mm.

[michael.h.f.wilkinson]

Michael at your F/10 scope 40mm is the lower power eyepiece you have?

Yes, it gets me an exit pupil of 4mm and 1.38 deg FOV. This is almost max for the C8, so a 50 mm does not make sense (even if it could fit a 69 deg FOV into 2";)).

[Hypernova]

I hope you don't mind me making things more complicated and recommending the Antares Speers-Waler series of eyepieces, they are very well corrected for fast 'scopes and are close to Naglers in terms of performance. They do a 17mm and a 13.4mm with 82 degree AFOV.

[russ]

I hope you don't mind me making things more complicated and recommending the Antares Speers-Waler series of eyepieces, they are very well corrected for fast 'scopes and are close to Naglers in terms of performance. They do a 17mm and a 13.4mm with 82 degree AFOV.

The Speers are superb and often overlooked. Best place for a secondhand Speers is in the US and there is sometimes a gem in the Cloudynights Classifieds. Overwise they are £149 new in the UK for the Series II.

[pleiades]

I hope you don't mind me making things more complicated and recommending the Antares Speers-Waler series of eyepieces, they are very well corrected for fast 'scopes and are close to Naglers in terms of performance. They do a 17mm and a 13.4mm with 82 degree AFOV.

Tom have you found a good review for Speers to take a look?

[russ]

Here we go:

The Speers-Waler 10mm - Review

Speers-Waler 10mm and the Nagler 9mm t1. Underdog Vs the Terminagler: - Review

Product reviews: Antares Speers-Waler 17mm eyepiece - by Matt Kelly - Helium

[pleiades]

Thanks Russ, that was quick I will spend tonight a lot of time for reviews. But from the first look, only the 17mm has 82 degree AFOV?

[russ]

There were two version available to start with. One with a 70deg fov and the other with 82deg. The 70deg was phased out to leave just the 82deg covering all focal lengths. Just make sure if looking at an early black barrel model that it is the 82deg version.

They were then given a minor make over a few years ago and shipped with silver and black barrels. And then updated again more recently with a Series II. The focal lengths offered with the Series II are slightly different to the original range.

The Series I 10mm 82deg is a classic and possibly the standout model. The 5-8mm Zoom is also one of the best zoom eyepieces available at any price point. The zoom is one of the few (i'm not sure but maybe only) zooms to offer an Ultra Wide Angle afov throughout it's zoom range. In fact it's apparent fov is larger than the fixed focal length models with an 84deg apparent field of view (i think it actually increases to 89deg at the 5mm setting).

[Hypernova]

I have my own opinion of owing one of the series 1 eyepieces that I bought off Russ a few months ago, and it is a good one. I have never looked through a Nagler, or any TV eyepiece for that matter, so I have no idea of how it compares to them but I have heard favourable comments made about them. In my f/6 dob, stars are pinpoint close to the edge, it is only in the last 10% or so where they begin to deform. It takes it until the very edge until it become troublesome, and I mean the very edge.

I would love to try it in a faster 'scope and see how it compares to other eyepieces with ultra wide FOV. So far I do not know of a direct head-to-head comparison between a Speers and a Nagler, it would be interesting to see one though

The only slight problem I have had with mine, which is the old model, is some fleck of paint settling on the inside lens surfaces, not much of a problem and only visible in daylight and when viewing the Moon (I am not a big lunar fan anyway). So far as I know this only a problem with the older ones and it has been rectified in the series 2.

Bear in mind that these quite a bit of in-focus though, it worked fine when I had my rack and pinion focuser and even better when I got a dual speed crayford from GSO that is slightly lower profile