Which 13-14mm eyepiece for DSO’s

[Mike_S]

I think I need one of these soon. With my 12” F5.3 dob a 13mm would give me exit pupil of 2.4mm. A 14mm would be 2.6mm.

the nearest I currently have to these are 9mm (1.7mm exit pupil) and a 20mm (3.75mm). Both of which are Myriad XWA’s.

what would you recommend? Might get the APM Lunt 100 degree 13mm. Not paying Ethos price new or used. 

Other contenders are Nagler 13mm, Delos 14mm, Pentax XW14mm, ES 82 degrees 14mm but really interested in what you would recommend, perhaps there is a great range of DSO eyepieces I’m overlooking? I’m building up Pentax XW’s and Delos for planetary. 

[A McEwan]

I have owned a Nagler 13mm T6 for many years, and it's one of the eyepieces I use in EVERY observing session and every telescope (apart from my Lunt). It is a superb performer, as you're probably aware, and very easy to use. It's just a great all-rounder.

 

I also used to own a Pentax XL14 back when I had a selection of the XLs (predecessors to the XWs). I actually can't remember any problems with it, but it was quite a long time ago. I enjoyed using the XLs and remember them being very comfortable and easy to use, with excellent clarity and sharpness.

 

Does it have to be wide-field? If not, a TeleVue 13mm "smoothside" Plossl is about as good as it gets at that focal length in terms of performance, and certainly in terms of bang-for-buck.

Good hunting!

Ant

[Mike_S]

2 minutes ago, A McEwan said:

I have owned a Nagler 13mm T6 for many years, and it's one of the eyepieces I use in EVERY observing session and every telescope (apart from my Lunt). It is a superb performer, as you're probably aware, and very easy to use. It's just a great all-rounder.

 

I also used to own a Pentax XL14 back when I had a selection of the XLs (predecessors to the XWs). I actually can't remember any problems with it, but it was quite a long time ago. I enjoyed using the XLs and remember them being very comfortable and easy to use, with excellent clarity and sharpness.

 

Does it have to be wide-field? If not, a TeleVue 13mm "smoothside" Plossl is about as good as it gets at that focal length in terms of performance, and certainly in terms of bang-for-buck.

Good hunting!

Ant

Yes it will have to be fairly wide field. I need some eyepieces between 11-17mm so a couple in that range really but probably start with 13mm. Either a new APM Lunt or a Nagler used maybe. Thanks glad the Nagler performs well for you as I hear mixed reports with the eye relief but I don’t wear glasses anyway.

[A McEwan]

1 minute ago, MSammon said:

Yes it will have to be fairly wide field. I need some eyepieces between 11-17mm so a couple in that range really but probably start with 13mm. Either a new APM Lunt or a Nagler used maybe. Thanks glad the Nagler performs well for you as I hear mixed reports with the eye relief but I don’t wear glasses anyway.

I do wear glasses, but always take them off to observe. Much simpler for me.

[Paul73]

I had a set of Delos with f4.7 and f4 Dobs. They were sold due to one of life’s little financial hiccups. After trying all sorts, i’m rebuying, as nothing else could match the Delos in these scopes. Although, I have not tried the Pentax XWs which I hear are similarly good.

Paul

Edited July 20, 2019 by Paul73

[Paul73]

Re. Plossls

I switched from Delos to TV Plossls. They are the best of a very old design. I found them sharp. I like them a lot, but 50° felt claustrophobic and very limited. Fantastic value for money. But, you would be hobbling your telescope by going the Plossl route. And, finding things is an absolute nightmare with only 50°. If budget were the limiting factor, my advice might be different, but if you have the budget, you can do a lot better.

Paul

Edited July 20, 2019 by Paul73

[Trikeflyer]

I have the Pentax XW10 and I love it. If I was looking in this focal length I’d go for the Pentax based on overall experience with the 10mm. That said, I’m sure there are plenty of reasons for choosing the other ones you have short listed, I just haven’t used them so can’t comment.

Good luck in choosing.

Steve 

[Oldfort]

It depends to a large extent on your budget but the Nagler type 6, 11 or 13 mm are really good, and you should be able to get a nice clean one for £160 - 180, used.

[jetstream]

Docter 12.5mm UWA (Noblex).

[Mike_S]

Thanks got some ideas to keep my eye out for. Leaning towards the  XWA 13mm or Nagler 13mm

Edited July 20, 2019 by MSammon

[John]

Mine in that niche are the Delos 14mm and the Ethos 13mm. Very, very good but lots of £'s as well of course. I've owned a number of the others mentioned above and they are pretty good too though.

[Mike_S]

I’ve decided to go for the APM Lunt XWA 13mm for now as I want a wide field. This would complete my eyepiece collection for now until I add some Delos in the long term. I can’t see a problem with my Myriads visually apart from the eye relief and awkward eyecup not being great but it’s okay, optically they seem spot on. Considered an ES 100 degrees 14mm but the weight put me off as it would need more balancing I think. Not worth it for one eyepiece. I think I’m parting with the idea of any Naglers too as I would end up with too many eyepieces that would be wasteful. 

[jetstream]

Very nice choice!

ps these offer better contrast than ES series EP's IMHO...

                                     or

NAGLERS...                                

Edited July 21, 2019 by jetstream

[Mike_S]

Yes I use my Myriads most. I can’t see a downside to them over my 5mm Pentax XW apart from comfort but I don’t have the most trained eye yet. I see no colour problems. Contrast seems spot on. I ordered a 7mm Pentax to fill a gap with my longer focul length scope but if I fill any more gaps I think it will be Delos. Hopefully I stop getting tempted but feel good for narrowing this down now. Going to a darker sky site with my brother when he is over for a couple of weeks in August so can’t wait. Will just try get that 13mm APM Lunt before then. 

Edited July 21, 2019 by MSammon

[jetstream]

1 minute ago, MSammon said:

I can’t see a downside to them over my 5mm Pentax XW

you will on the planets and moon once you have your scope well collimated under VG seeing....but thats OK they (XW's) are sharper than ETHOS too,

[Mike_S]

1 minute ago, jetstream said:

you will on the planets and moon once you have your scope well collimated under VG seeing....but thats OK they (XW's) are sharper than ETHOS too,

Yes I got my Cheshire now and haven’t thought about collimation since because it’s been cloudy. I’ve deleted fancy collimation stuff from my wish list and went back to sorting my eyepieces and filters. I’m alright for filters for now too so getting there. 

[jetstream]

Just now, MSammon said:

Yes I got my Cheshire now

Excellent!

A cheshire is your friend and a newts best friend.....

A slight amount of miscollimation (primary espc) will defeat all your VG ep purchases for lunar planetary. However, collimate well, cool it well, get it under dark skies with good seeing and hang on!!

[michael.h.f.wilkinson]

I have the Delos 14mm, use it a lot, and love it to bits. Outstanding performance over the entire field, and huge viewing comfort. Very similar to the Pentax XW 5, 7, and 10 mm I have. The XW 14 apparently has quite a bit of field curvature (intentionally, to match that of the spotting scopes they were designed for).

[John]

2 hours ago, jetstream said:

you will on the planets and moon once you have your scope well collimated under VG seeing....but thats OK they (XW's) are sharper than ETHOS too,

I agree although these are both superb eyepiece ranges. Thats why I have both XW (10, 7, 5 and 3.5) and Ethos eyepieces (21, 13, 8 and 6mm) - best of both worlds and complimentary focal lengths

I didn't keep the Ethos XW 4.7 and 3.7 AND the Pentax XW 5 and 3.5mm though - after 6 months of comparing them I felt that the XW's were slightly sharper and showed slightly less scatter around bright objects. So I let the Ethos SX's go to new homes.

As well as excellent collimation, excelleng seeing condtions, challenging targets and an experienced eye are needed to detect the slight differences in performance. Much of the time, at least here in the UK, the seeing conditions become the leveller 

[Mike_S]

13 minutes ago, John said:

I agree although these are both superb eyepiece ranges. Thats why I have both XW (10, 7, 5 and 3.5) and Ethos eyepieces (21, 13, 8 and 6mm) - best of both worlds and complimentary focal lengths

I didn't keep the Ethos XW 4.7 and 3.7 AND the Pentax XW 5 and 3.5mm though - after 6 months of comparing them I felt that the XW's were slightly sharper and showed slightly less scatter around bright objects. So I let the Ethos SX's go to new homes.

As well as excellent collimation, excelleng seeing condtions, challenging targets and an experienced eye are needed to detect the slight differences in performance. Much of the time, at least here in the UK, the seeing conditions become the leveller 

What Delos do you have? I don’t plan on buying more Pentax. Not that I’ve got a problem with them but if I feel I wanted to try get a sharper view then I would be tempted to try Delos next just to see, first in some of the sizes I don’t have at the moment. It seems a coin toss or slight personal preference between XW’s and Delos under 14mm. 

Edited July 21, 2019 by MSammon

[John]

36 minutes ago, MSammon said:

What Delos do you have? I don’t plan on buying more Pentax. Not that I’ve got a problem with them but if I feel I wanted to try get a sharper view then I would be tempted to try Delos next just to see, first in some of the sizes I don’t have at the moment. It seems a coin toss or slight personal preference between XW’s and Delos under 14mm. 

I have the 17.3 and 14mm Delos. I've read a lot about the field curvature of the 14mm and 20mm Pentax XW so I decided to go for Delos for the longer focal lengths in my 1.25 inch set. I've been very happy with the 10, 7, 5 and 3.5mm XW's but from what I've read, I suspect that there is little or nothing to choose between the XW's and the Delos equivalents. The 17.3 and 14mm Delos have a focus position that is closer to the XW's though, than the shorter Delos eyepieces, a factor that has an attraction for me in minimising the refocusing needed when swapping eyepieces between a Delos and an XW.

To get a sharper view than a Pentax XW, a Delos (or a Delite) I suspect you would need to move to one of the so called "top tier" specialist planetary eyepieces such as a Zeiss ZAO, a TMB Supermonocentric, A Pentax XO or an Astro Physics SPL. Its possible that a Leica ASPH zoom might be a touch better than the XW's as well although I can't say that I found that in any obvious sense when I owned that zoom and compared it with the XW's.

Bear in mind that we are talking about very, very suble differences in performance here. It's not a case of eyepiece A showing something that eyepiece B won't show, more  slight differences in presentation and quite often personal preference that vary target to target.

 

[Mike_S]

1 minute ago, John said:

I have the 17.3 and 14mm Delos. I've read a lot about the field curvature of the 14mm and 20mm Pentax XW so I decided to go for Delos for the longer focal lengths in my 1.25 inch set. I've been very happy with the 10, 7, 5 and 3.5mm XW's but from what I've read, I suspect that there is little or nothing to choose between the XW's and the Delos equivalents. The 17.3 and 14mm Delos have a focus position that is closer to the XW's though, than the shorter Delos eyepieces, a factor that has an attraction in minimising the refocusing needed when swapping eyepieces.

To get a sharper view than a Pentax XW, a Delos (or a Delite) I suspect you would need to move to one of the so called "top tier" specialis planetary eyepieces such as a Zeiss ZAO, a TMB Supermonocentric, A Pentax XO or an Astro Physics SPL. It's possible that a Leica ASPH zoom might be a touch better than the XW's as well although I can't say that I found that in any obvious sense when I owned that zoom and compared it with the XW's.

Bear in mind that we are talking about very, very suble differences in performance here. It's not a case of eyepiece A showing something that eyepiece B won't show, more  slight differences in presentation and quite often personal preference.

 

I’ve learned a bit there about the focul positions thank you. I heard about the field curvature on the larger XW’s too. I’ve done a lot of searching and reading back some great old discussions on here.

[Mike_S]

When do you use the 14mm Delos over the 13mm Ethos?

[michael.h.f.wilkinson]

I have Delos 6 and 8 mm EPs, sitting between my XW 5, 7, and 10 mm EPs. This is perfect to match magnification to seeing conditions on planets. I use parfocaliser rings on the shorter two Delos EPs to match them with the XWs. Works a treat. I cannot really tell any difference in performance between them. I cannot get the Delos 14 mm parfocal with the XWs, however, because it focuses a good deal further inwards.

[John]

2 hours ago, MSammon said:

When do you use the 14mm Delos over the 13mm Ethos?

With the 12 in dob it's the 13mm Ethos practially everytime.

The Delos eyepieces are great and I use them in my refractors often but, for me, the hyper wide eyepieces and medium to large aperture dobsonians are a marriage made in heaven