ES 68degree or Meade hd60 or Celestron x-cel?

[Starlord19]

I currently have a 25mm BST which is great in my f10 sct but seems to struggle a bit in my f5 newt. I was considering changing it for the baader hyperion but I've since read that they don't like fast scopes either. 

I've narrowed it to the ES 68degree 24mm at £98, the Meade hd60 25mm at £95 or the celestron x-cel lx 25mm at £59. 

My question is, has anybody got any experience with these ep's in anything like an f5 reflector. And if so, are the Meade and ES ones really worth nearly twice that of the Celestron? 

[DevonSkies]

I use the X-Cel LX in an f/5 reflector, and find it very good. A huge improvement over the 25mm BST, that's for sure. Hope that helps!

[Davesellars]

I'm using the 24mm ES68 with my 12" dob (f4.9).  I was able to take a good look at the eyepiece on Saturday night and how it was performing without using the Paracorr.  This eyepiece performs excellently in my f7.5 refractors with no optical aberrations whatsoever however at f/5 is somewhat harder on this EP though!  It does suffer a small amount of astigmatism from 90% and obvious coma more towards the edge but it's not really intrusive.

[John]

The ES 24mm 68 is the best of those, having tried them all. Don't expect a massive leap in performance over the BST 25mm though, just better edge correction.

[Starlord19]

Thanks everyone. I think that I will disregard the Meade, as it's too similar in specs to the Celestron to justify the jump in price. I am happy to hear that the Celestron is an improvement over the BST, especially from someone who has used both. Initially I was leaning towards the ES68 24mm but I don't want to pay £40 for an extra 8 degree afov (is it worth it?) only to find that it's not that sharp to the edges!

[John]

Just to be clear, I would recommend the ED 24mm 68 over the others. To get eyepieces that are absolutely sharp right to the edges in an F/5 newtonian you probably need a Tele Vue / Pentax budget but the ES 24 / 68 is the next best that I've used. Even then you may need a coma corrector to eliminate the scope produced coma from the field edges if that bothers you.

There were rumours around that the Meade HD60 eyepieces were the same as the Celestron X-Cell LX's and their specs are very similar. They are not bad eyepieces but the ES 24 / 68 is a cut above them.

My note about not expecting the BST 25 to be "blown out of the water" relates to the improvements being subtle as the costs rise - a sort of "expectation management" I guess !

[Davesellars]

I don't have another 24mm wide-field to compare but the ES68 does perform very well in brightness of the image and neutral colour.  It is also very sharp across the majority of the FOV.  It's very well built and not too heavy.  I use this as my eyepiece for finding the DSOs

I'd be interested to know what difference there is between this and the 24mm Panoptic though when it comes to performance on DSOs.  As John says the jump to the next level is rather more expensive.

[John]

I've just moved from the ES 24 / 68 to a 24mm Panoptic. The Pan is a bit sharper in the outer 10-15% of the field in my F/5.3 scope but other than that I've not seen any differences in performance to note.

 

[Starlord19]

I can handle a bit of distortion at the edge as long as that's where it stays. My main fear is that if I pop for the ES68 and the outer 8 degrees is distorted then I could've saved the extra and got the 60 degree Celestron (as long as that's sharp across). 

I think, as with most things, that there is a law of diminishing returns. Where there is quite a hike in cost for a small increase in performance, it's just a case of what's more important to you I suppose, a cost/benefit analysis is required! 

[John]

There certainly is a law of diminishing returns !

I'm not sure that the Celestron will be completely sharp all the way across the field at F/5 either though.

Incidently, I paid £75 delivered for the ES 24 68 from a German retailer.

 

 

[Starlord19]

That's a good point about the Celestron, I've got a feeling that to get a sharp view across the field will be beyond my budget. The ES68 was at the top of my price range anyway, thanks for everyone's help. 

[F15Rules]

Get the ES 24mm 68. It's a no brainer, I think it is a lot better than the Celestron.

I've only let mine go recently as I now have a Vixen LVW 22mm which is even better.

The ES has some of the brightest and best coatings I've ever used.

And the ES will be sharp across the whole of the 60 degree field offered by the Celestron.

And finally, the build is MUCH better, closer to Tele Vue or Pentax than Celestron.

Dave

[andrew63]

You might want to consider a maxvision,meade,es  20mm 68.  It will show nearly the same amount of field as the celestron 25.  The max are nearly all sold out, but for £60 are superb.  I have recently used one in my F5 refractor and the stars were sharp right to the field stop and craters sharp at the field stop.  I'm not sure of what difference using a F5 newtonian would make ?

https://www.telescopehouse.com/explore-scientific-68a-maxvision-eyepiece-20mm.html

andrew

[Louis D]

You might like to read the 24-26 mm Eyepiece Comparison by Bill Paolini on CN.  It covers some of the mentioned eyepieces and quite a few others.

[TheLookingGlass]

On 12/5/2016 at 08:32, Starlord19 said:

I currently have a 25mm BST which is great in my f10 sct but seems to struggle a bit in my f5 newt. I was considering changing it for the baader hyperion but I've since read that they don't like fast scopes either. 

I've narrowed it to the ES 68degree 24mm at £98, the Meade hd60 25mm at £95 or the celestron x-cel lx 25mm at £59. 

My question is, has anybody got any experience with these ep's in anything like an f5 reflector. And if so, are the Meade and ES ones really worth nearly twice that of the Celestron? 

I've owned the 24mm ES 68 and I now own the 25mm Celestron X-Cel LX. The latter has a lot better eye relief and correction IMO.

 

The 24mm ES 68 shows field curvature, coma and slight astig. 

[cloudsweeper]

I have the ES 24/68 and am very satisfied with it.  And it looks the business!

Eyepiece comparison threads are always interesting and informative.  As @John said, a law of diminishing returns applies here, and there is also a fair degree of subjectivity: something that irks one observer might be perfectly acceptable to another!  (A bit of field curvature in a wide angle EP doesn't bother me too much, for example!)

Doug.

[John]

I owned an X-Cell LX 25mm for a short while as I said earlier. I thought it OK but it was very prone to picking up and showing specks of dust when viewing bright objects. This is because the optical design uses a heavily convex lens right on the focal plane of the eyepiece. It's practically impossible to keep dust free I found.

I much preferred the ES 24mm 68 degree eyepiece that I owned recently. Well corrected in fast scopes, well made and for well under £100 too.

[alan potts]

I can only speak about the full range of Meade SWA or 68 dgrees eyepieces that I once owned. The ExSc are the exact same elements and even if coating are different there will not be much between them. All of the Meade range perform well apart from at very fast scope speed, I guess the ExSc will do the same as well, I would not personally recommend them much below F 5, I started to see faults at the edge of field at F 5.26 but I was looking for it at the time, my favourites were the 28mm and 40mm which many a time I wish I still had.

Alan

[spaceboy]

It's a shame about the 25mm BST as this really is a weak link in an otherwise strong chain of budget performers. I have owned both the 24mm ES68° Argon purged and ES 24mm Maxvision and I personally found the Maxvision the better of the two both in optical performance and comfort due to the screw up eye guard allowing better positioning off the eye relief. The Maxvision is though becoming harder to come by so the more expensive ES24mm may be the way to go if your looking to quickly replace the 25mm BST. The ES24mm are very well made but my example seemed to lack the edge correction that the Maxvision offered. Others have also reported similar experiences but what ever the case there will be an aberration improvement over the 25mm BST. Although it's worth mentioning that coma will still be present in an f/5 newt so it would ultimately be down to personal preference to how much an improvement it actually makes.

[John]

Coma will be present in an F/5 newt, agreed. If the eyepiece is really well corrected and has a wide field you can see it. If the eyepiece shows some astigmatism then that can mask the scopes coma. Sometimes you see a blend of both aberrations so it's hard to tell what the cause is.

 

[alan potts]

It is perfectly true what John says about coma though I have looked through a 24mm SWA Meade, a different one to the one I owned, that had a little astigmatisum at about F 5, that is my F 4.3 scope with a Paracore, without the Paracore I have to say I found it fairly awful at the outer field, I did a review of the two which is in the equipment section somewhere.

Though I have to say using such eyepieces like 35mm and 24mm Panoptic's which also have 68 degrees field, the coma was not that bad at the faster setting F 4.3 and TV handle other aberations very well, I could live with it in fact, it's when you start using 82 degree FOV and larger the wheels come off and it really annoys me.

Alan