25mm Celestron X-Cel LX

[Nightspore]

The Celestron X-Cel LX has an apparent field of view of 60º. There are six internal elements. I have no information on the amount of groups. The eyepiece body is made of black anodised aluminium with orange and white lettering. Celestron declares that it has a 16mm eye relief. They also claim the X-Cel LX are parfocal with the others in the range. Although this is not strictly true in my experience with them. I paid £109 for the 25mm back in early April. 

 

 

The housing (including barrel) is approximately 85mm in length and 95mm with the ‘twist-up’ eyeguard extended. It has a generous eye lens and I make the field stop about 26mm. The housing sports a novel equatorial treaded rubber grip reminiscent of a tractor tyre. The barrel includes a filter thread, adequate baffling and a shallow undercut. The eyepiece weighs around 170g according to my scales and is supplied with its own bolt case.  

 

 

I now own several X-Cel LX eyepieces. About six years ago I acquired the 9mm.

 

 

It was the first X-Cel LX I bought. As it had a 60º FOV, I tended to use it predominantly as a planetary eyepiece, often in conjunction with a Barlow. It was only years later that I discovered just how good the 9mm X-Cel was for rich field observing, particularly in short tube refractors. 

 

 

The original Celestron X-Cel eyepiece range were reputedly among the worst designed eyepieces in the world. They were not successful. Celestron eventually released a new range with the X-Cel brand name but with the letters ‘LX’ added. So, no confusion there then! These LX versions generally have a very good reputation. Although I have had quality control problems with them in the past. Three or four years ago I had to return three 7mm focal length LX’s consecutively due to visible debris in the field. This was a known problem with some other focal lengths as well. Apparently due to a bad batch. I’ve not had the same problem with recent purchases.

 

 

X-Cel LX eye lens dust caps are very close fitting. This seems to be the same throughout the range. The upside is that the cap won’t come off if the eyepiece is in your pocket. The downside is that you may lose a fingernail trying to remove the cap in the first place. Okay, maybe it’s not that bad. The field lens caps are fine. 

 

 

I got first light with the 25mm X-Cel LX in my 72ED DS Pro Evostar around 00:30 BST on June 13th. It gave 16.8x for 3º, 34’ FOV and a 4.3mm exit pupil. My main observing was in the Summer Triangle and the rich star fields within and around it. Collinder 399 (Coathanger Cluster), M57, M29 and M27 were all duly observed. I also spent some time in Cassiopeia. I could easily see both globular clusters in Hercules. I even found a low Andromeda Galaxy. I used an Explore Scientific broadband OIII filter for the Dumbbell/Applecore Nebula and the Veil Nebula. The overall sharpness, visual acuity, contrast and colour separation were superb. It is a well corrected eyepiece and showed very little edge astigmatism and no lateral colour. I’d say it had a slight advantage over my 25mm TS Optics Planetary HR which has a similar field of 58º. I found the eye placement excellent with no problems, although the 16mm eye relief is a little long for me. The twist-up eyeguard helped with ameliorating this however. I’ve always liked the X-Cel eyeguards. They have an elegant simplicity that works well during actual observing.

 

 

Overall this is an enjoyable eyepiece to use and I specifically bought it for the 72ED, primarily due to its comparatively light weight. I’ve had it out in the field for three sessions now. It’s definitely a keeper.

[Caldwell 14]

A very late reply to this thread. I had a full set of these around a decade ago. I thought they were really very good eyepieces. I did have a little issue with the rubber eyecups coming loose, which I sorted with a specialist double sided tape. I only sold them when the TV bug hit (now cured). I use a Baader Zoom and Baader Barlow these days for just about everything really. 

[Nightspore]

20 minutes ago, Caldwell14 said:

A very late reply to this thread. I had a full set of these around a decade ago. I thought they were really very good eyepieces. I did have a little issue with the rubber eyecups coming loose, which I sorted with a specialist double sided tape. I only sold them when the TV bug hit (now cured). I use a Baader Zoom and Baader Barlow these days for just about everything really. 

 

The 9mm was the first I ever bought a few years ago. I mainly used it for lunar/planetary but was surprised how good it was for general astronomical observation. I have the BHZ/Barlow as well. I've had entire nights just using that.

[Caldwell 14]

12 minutes ago, Nightspore said:

 

The 9mm was the first I ever bought a few years ago. I mainly used it for lunar/planetary but was surprised how good it was for general astronomical observation. I have the BHZ/Barlow as well. I've had entire nights just using that.

 

I really dislike changing eyepieces, hence the zoom. The Celestron Zoom is a very good cheaper alternative. You used to be able to get a BST/Starguider version of the same eyepiece, cheap as chips and plenty good enough for most night out for those on a budget

[Nightspore]

1 hour ago, Caldwell14 said:

 

I really dislike changing eyepieces, hence the zoom. The Celestron Zoom is a very good cheaper alternative. You used to be able to get a BST/Starguider version of the same eyepiece, cheap as chips and plenty good enough for most night out for those on a budget

 

The Celestron, Meade and other generic name zooms are probably all made by the same OEM. 

 

 

The 'Orion' 7~21mm zoom is very good. The BHZ Barlow fits it perfectly.

 

[Caldwell 14]

Eh, that's the one alright. 

[Nightspore]

I have other zooms. I went through a bit of a phase lol.

 

[+Glafnazur]

I've never used a zoom, in your experience is the view as good as a fixed eyepiece?

[Nightspore]

3 hours ago, Glafnazur said:

I've never used a zoom, in your experience is the view as good as a fixed eyepiece?

 

Now there's a question. There is much debate about this. A lot depends on the zoom of course. In my experience the Baader and Pentax zooms are as good as most decent eyepieces. The main disadvantage is that most zooms have a limited field at their longest focal length. 

 

 

 

I find the Celestron zoom every bit as good as any of the GSO or Barsta Plossls I have. The 'no name' Sky-Watcher 7-21mm displays some false colour.

 

 

The 3-6mm Nagler zoom is as good if not better than TV Plossls. The Nagler is 50 degree from 6mm to 3mm. 

 

 

The Orion 7-21mm is as sharp and bright as the Celestron zoom at least. At 21mm it only has about 40 degree FOV. I use it a lot for lunar/planetary, mainly between around 12-7mm. Zooms are a bit specialist in many ways.

 

 

The BHZ and Pentax XL are probably the best for general astronomy. 

 

 

Edited February 17, 2022 by Nightspore

[+Streetbob]

Thanks to this thread I’ve rediscovered my Baader zoom mkIII. And a joy to use it was.  The views are as good as the Explorer Scientific eps I use. The reason I fell out with it was the eye guard. It falls off when I remove the dust cap. Grr

[Nightspore]

1 hour ago, Streetbob said:

Thanks to this thread I’ve rediscovered my Baader zoom mkIII. And a joy to use it was.  The views are as good as the Explorer Scientific eps I use. The reason I fell out with it was the eye guard. It falls off when I remove the dust cap. Grr

 

Baader dust caps can be weird. When I first bought the BHZ the dust cap was really difficult to remove. After using it once some huge debris could be seen in the FOV (I hadn't seen it when I daylight tested it). So I returned it. The replacement had a normal fitting cap.

[+Streetbob]

I have found the solution.  Baader do a threaded eye guard that fits the mk3.  

 

https://www.firstlightoptics.com/baader-planetarium/baader-morpheus-rubbermetal-foldable-eyecup.html

 

 

[Nightspore]

On 28/02/2022 at 14:25, Streetbob said:

I have found the solution.  Baader do a threaded eye guard that fits the mk3.  

 

https://www.firstlightoptics.com/baader-planetarium/baader-morpheus-rubbermetal-foldable-eyecup.html

 

 

 

 

I bought one of those for my 14mm Morpheus as it was one of the old winged type originally. Be wary of the rubber detaching from the metal thread part as there is a fair amount of grease that could transfer to the eye lens.