9mm Nagler vs 10mm delos

[morls]

Hi,

I'm looking for a quality eyepiece that I can use for high magnification in my 180 mak. I currently have an ED 8mm, but at 338x I don't think it will be used a lot of the time.

The 9mm Nagler will give me 300x, which might still be pushing it, while the 10mm delos will give 270x. Most observing is done in suburban Melbourne, with the occasional trip to darker skies.

I'm leaning towards the delos, as I think this will get the most use, but I'd be very interested to know what more experienced members think as well. At this stage I'm only considering televue eyepieces, so would love to hear of others' experiences with these in a 180 mak.

Cheers

Stephen

[GUS.K]

Hi Stephen, I use Pentax XW 10 and 7mm, as well as a Delos 6mm.I also use TV Delites 11 and 7mm. If you can live with a 60 degree view, the 11mm Delite is great. When seeing allows, the Delos 6mm is exceptional on the moon. I recently got an ES8.8mm 82 degree, also a great eyepiece for Lunar viewing. The Radians are good as well, the 14mm (192x) being the most used EP in my SW180 Mak.

[Startrek]

Hi Stephen

I’ve been using Televue eyepieces for 2 years now and have Ethos, Delos and Panoptic which I use in my 10” dob and 6” newt
I sold my 7mm delite when I looked through some high power Delos
My favourite high power eye pieces for lunar and planetary viewing would be my 6mm and 10mm Delos and 8mm Ethos , truly outstanding eye pieces
When viewing permits I bring out my 4.7mm Ethos and 4.5mm Delos
Delites are a superb eye pieces but not in the same league as their bigger brothers
I also have the full range of Powermates which I use to complement my eye piece range and also use for planetary and lunar astrophotography

You pay for what you get with teleview ,I wouldn’t use anything else ,they are lifetime quality investment

Martin

[morls]

Thanks Gus and Startrek,

I also think they're a lifetime investment, and am pretty comfortable with the notion that whether televue, pentax or similar the performance will be top notch. My experience has been with televue, so for now I'll keep building my basic eyepiece set with these. My 35mm panoptic is a wonderful eyepiece. The radians are discontinued aren't they? I'll have to keep a look out for a used one.

I've read interesting comparisons between nagler and delos, most suggesting the delos, being a more recent design, has the edge over the nagler. I'm interested to know whether there is a case for either 300x or 270x being a magnification useful 85% of the time? Is there a generally agreed magnification limit for typical urban conditions?

[Startrek]

Stephen,
From my experience the night sky is a continuous moving target as far as seeing conditions, it changes from night to night , season to season and location to location but if I had to put a general magnification limit it would be the following -

Suburbs (sa 30 to 40 km from CBD ) 180 x magnification

Regional or Rural town 250 x magnification

Dark site + 300 x magnification

I don’t know if this helps as like I said the seeing conditions are ever changing phenomena. There have been some nights in Sydney where I used a 4.7mm Ethos ( 265 x mag ) and observe Jupiter in excellent detail.

I would recommend buying a powermate ( say 2 x) at some stage to give you some flexibility with your eye piece collection

Good luck !

Martin

[Madanie7]

Sooooo. What did you buy Stephen? :D

[morls]

Well, I haven't made a final decision yet, but I've ordered a 2" Baader BBHS mirror diagonal. If I'm going to do this, I'm going to do it properly and make sure all parts of the optical chain are the best I can afford to get. The diagonal is around the same price as a Delos, so it's going to take a while to get this paid off. Meantime I'll keep considering options.

[Madanie7]

Is it purely magnification that's your driving force.
Any design, FOV, eye relief etc coming into it?

Any reason you chose the Baader over Tele Vue?

[morls]

I'm looking for high magnification, neutral colour and good eye relief.



As far as the Baader, I've been checking out reviews and this seemed to rate very highly. I also like the click-lock.


Cheers
Stephen

[ab1963]

Hi Stephen
Smart move I have this diagonal and is without any doubt in my mind the best mirror diagonal I have ever used ,Coupled with a Tak FS60Q,Nikon Nav 17mm HW the views I’ve had with this configuration are no less than amazing

[Madanie7]

Yeh nice. I am thinking either of these two as well as an additional 6mm Delos.
I like the long eye relief of the Delos

[morls]

Good to hear of your experience Andrew. Looking forward to getting mine mid-November (ish...)

[morls]

The Baader diagonal arrived a few days ago, and it must be fantastic because we've had record hail storms and cloudy nights ever since...:lol:

[Madanie7]

That's generally how it goes.
Have you managed to use it yet? Notice a big difference?

[morls]

I've used it, and all I can say is that over the last couple of nights I've had AMAZING views of the moon at 330x. I don't know if this is solely because of the Baader, but I do know that before I got it I wasn't able to use this magnification, ever.


I'm not a very experienced observer so it's difficult for me to judge exactly how much difference it's made. All that really matters to me is that the views are AMAZING. First light with the diagonal was a couple of nights ago, trying to track down the three craters Alex put out as a challenge in his beginner's thread. I spent a long time at 330x in the area, and slowly the detail started to appear to me. It was a really amazing experience, and the views blew me away. Like I said above, I've never been able to use this magnification before, but in this session I was staying there and the resolution was top notch at all times.



So, I'm very happy with this purchase :D:D:D:D:D:D

[Wavytone]

Having had three of these scopes I can say a lot depends on how good your particular scope really is. The best of the ones I had often handled an 8mm - 340X or 1.8 per mm of aperture quite well.

Mental’s M715D can manage 2.5X per mm, as does my MK91.

This is primarily a function of the quality of your objective (ie the scope), not the eyepiece. For example Dawes recommended 80X per inch of aperture / 3X per mm - which indicates that some of the old refractors used 100 or 200 years ago did indeed have exquisite objectives despite the rather modest eyepieces (Huygens or Ramsdens) and lack of modern coatings.

[morls]

That's interesting Nick. The latest observations with this scope have been encouraging - last night I was again able to use the 8mm on the moon, and I don't think the seeing was particularly good. This is twice in as many sessions after getting the diagonal and tweaking the collimation, whereas before these changes I hadn't been able to use the 8mm at all.
I'm going to keep my options open regarding which focal length Delos I'll get in this range of magnification, and might try some cheaper options at 9, 8 and maybe even 7 (380x) to see what this setup is capable of before putting down the big bucks on a premium.
I've also ordered in a Baader Steeltrack focuser, so I'm slowly getting things lined up to push the optics.

[Don Pensack]

Why add the rear mounted focuser? Adding the length on the back end will increase the focal length of the scope and narrow the true field of each eyepiece. That is an add-on oriented to the astrophotographer who needs to make sure the image doesn't move when focusing, but that's not important for visual use. I would have spent the money on eyepieces.

[morls]

Hi Don, the main reason is because I want to have finer control than I can get with the internal focuser, and the elimination of mirror shift will be a bonus as well.

[Don Pensack]

Then replace the focuser with a Starlight Instruments 2-speed focuser replacement or add the JMI 2-speed add on. Both of those give you very fine control without adding focal length to the scope.
For every 10mm of additional rear length you add, you add 31mm to the focal length of the scope. You'll end up with an even longer focal ratio than the long f/ratio the scope already has.
Your scope already has a narrow field of view; you probably don't want to make it even narrower.

[morls]

Although hese both look excellent, there are a few reasons behind my choice of the Baader. Starlight is out of my league cost-wise, at $520USD plus $180USD adapter for 180 Mak. The JMI is still over $100 above the cost of the Baader.
The JMI has around 15mm drawtube travel compared to 30mm with the Baader, making it less flexible for other scopes as I build my collection. The baader also has greater payload capacity, and although I'm not going to get close to the 6kg limit I might in the future.
The baader at minumum draw adds 90mm rear length, compared to 63mm for the JMI. This 27mm rounds out to about 83mm additional rear length with the baader over the JMI, before any focuser extension happens. So, the Baader at minumum extension makes the 180 Mak f/16.5, the JMI f/16.
I'm not sure how this difference would manifest in the real world - using an online calculator the fov with Baader and 35mm panoptic reduces from 0.88° to 0.8°.
I'm still comfortable with my choice given the lower cost, larger drawtube travel and greater payload capacity of the Baader. I wasn't sure of the exact impact on focal length, so thanks for pointing that out.

[Don Pensack]

You completely misunderstood.
I wasn't talking about A Starlight Instruments rear-mount focuser at all.
I was talking about replacing the actual focusing knob with a 2-speed focus knob, leaving the back of the scope intact at whatever shorter length the visual back yields.
The JMI one, I am sorry, is no longer available:
https://tinyurl.com/ybz4q6m4
The Starlight Instruments one may or may not be available for the Mak:
http://starlightinstruments.com/store/index.php?route=product/category&path=37_80
Or even this:
http://www.scopestuff.com/ss_foc1.htm

If confined to the rear-mount focuser, I see nothing wrong with your original choice.

[morls]

I see what you mean now. Yes, I considered this type of fine control focuser, but was again put off by the price - the starlight comes in at over $500AUD, and would only be of use for the Mak. I've been using a home-made adaptation for the existing knob that gives much finer control but I really miss being able to dial back and forth without any shift so I can really get things sharp. Maybe it's my technique, but I'm hoping this upgrade will take focusing on the Mak to a new level.

[morls]

Well, a decision has been made, though not what I imagined when starting this thread. I've just ordered a 12mm Nagler type 4. I've decided to go for a premium 8mm down the track, but in the meantime my 8mm ED will suffice. The 12mm will give me 225x with 0.36* tfov, so should get a lot of use.
Thanks to everyone offering advice :thumbsup:.

Stephen

[morls]

Another change, due to the 12mm Nagler being discontinued. I'm getting a 16mm Nagler type V as mid/high power option, to go with my 35mm Panoptic. I suspect I'll be adding something around 12mm and then replacing my ED 8mm down the track.

[Madanie7]

Interesting considering you were looking for magnification originally.
What brought about the change?

[morls]

A few things...I already have an 8mm, and although it's not top quality it does the job until I get an 8 or 9mm premium. I'm going to keep note of how many times I can use the 8mm over the next few months, as I don't want to spend premium $ on a seldom used eyepiece.
This 16mm will replace the ok-quality 15mm I have. At the moment I have a 35mm, 15mm and 8mm. I have a loose system in mind for my basic eyepiece setup regarding FOV and exit pupil: the 35mm Pan gives me 2.3mm exit pupil, 77x with 0.82°. I was looking at something around half this FOV, and had narrowed my choice down to the 19mm Panoptic (1.3mm exit pupil, 145x with 0.45°) or the 16mm Nagler (1.1mm exit pupil, 167x with 0.47°). I decided on the Nagler because of the greater magnification and slightly larger FOV.
In the meantime, the 10% off sale at Bintel came up, and I wanted to take advantage of that. Only problem was it applied to stocked items only, and the choice of Nagler was limited to 12mm. I'd also found out the 12mm was discontinued, so I thought this might be a chance to get this before new stock ran out. I'm not terribly fussed about the order in which I get my basic set together, and 12mm seemed a good fit between 16mm and 8 or 9mm. I didn't want to go straight for the short f/l eyepieces as I'm still in two minds.

As it turned out, the 12mm wasn't available after all, and so after a phone conversation with Don at Bintel (who was very helpful! :thanx:) I was able to substitute the 16mm in the order I'd placed.
So, it looks like my eyepiece set will be 35mm Pan, 16mm Nagler, 12mm Delos, 8mm Delos (likely). This will give a progression of 0.82°@77x, 0.47°@167x, 0.32°@225x and 0.21°@338x.
Sorry for the long-winded answer, but you did ask...:)

[Madanie7]

I like detailed responses. As I am fairly new to learning the ins and outs of eyepieces (you'd notice this by the questions I ask) I like to know how people think about their eyepiece collection.
I am building my eyepiece collection and I like to know that I am getting the best possible eyepieces both in quality and fit for my set up.
These eyepieces aren't cheap so I hate the thought of someone saying "you should have bought this instead".....so I ask lots of questions lol

[morls]

I agree...I'm pretty new to all this as well. My thinking is that I'm going to be buying and selling eyepieces as I continue, so getting a premium and getting to know its character is part of the journey. If I end up selling one to fund another, at least I'm getting closer to understanding what it is I'm looking for. I much prefer a hands on approach to these things, plus I just like good gear!

[astro744]

Note the eye relief of the 16 Nagler, Type 5 is tighter than the 35 Panoptic, 12 Delos & 8 Delos. Not for eyeglass wearers and even without glasses you are up close with this eyepiece. It is a very fine eyepiece though. Did you consider 14mm Delos or if you want Nagler then 13mm, Type 6 which has a bit more eye relief than the 16. See http://www.televue.com/engine/TV3b_page.asp?id=214

The 17 Nagler, Type 4 or 17 Delos are also good options for longer eye relief.

With regards to buying and selling until you find something you like sounds good in theory but you will find the only way to do it properly when comparing is to gave both or more alternatives at hand when you compare. Unfortunately sometimes you have to sell first to buy the alternative only to repurchase the first option again later. This is when it gets expensive!

Another thing to remember is that you will eventually end up with extra and different telescopes with different focal lengths and optical characteristics. If buying for magnification alone for one telescope you will find a completely new series of eyepiece focal lengths works better with another telescope. Also remember if you keep the apparent field of your chosen eyepieces the same then the true field of view and magnification change with the same ratio.

Whatever you choose, enjoy!

[Kunama]

I found that the actual eye relief of the Nagler 16T5 was about 9mm, too tight for me, but a nice sharp eyepiece for those who can deal with the ER.

[anj026]

I couldn't cope with the 16mm type 5 either. Just not comfortable for more than short sessions. If it all possible try to test it yourself before buying.

I still have a 17mm type 4 which I like very much except for the weight of it.

The 13mm type 6 is a wonderful compact eyepiece and barlows well.

[morls]

I'm reasonably confident the eye relief will be ok - I had a 13mm Nagler a while back with around 12mm eye relief, and found this very comfortable. I don't wear glasses...

[morls]

Hi Astro,

I did consider these, and may well end up with either or even both in the future! In the meantime I wanted larger FOV, hence the 16mm.


I've been using this calculator from Tele Vue:
http://www.televue.com/engine/TV3b_page.asp?NoBack=True&id=212&plain=TRUE&focal_length=2700&fl_unit=mm&aperture=180&a_unit=mm&fratio=&_2in=yes&Nagler=TRUE&Delos=TRUE&Panoptic=TRUE&title=&sortby=SortTrueField&SUBMIT1=CALCULATE#results

[ausastronomer]

Hi Andrew,

I would rate the Nikon Nav 17mm HW as the single very best eyepiece I have ever used, just slightly in front of the 12.5mm Docter. I put both of those just slightly ahead of Pentax XW's, Delos and ETHOS which are also at the top of the tree.

However, notwithstanding it's a TAK, I have a heavy heart that such a wonderful eyepiece lives in a 60mm Telescope :) I hope it also finds focuser time in something somewhat larger.

Cheers
John B

[ab1963]

Hi John
I also have the 12.5mm Docter and Swaro 25x50 w zoom with a Baader vip modular barlow and that's it apart from bino pairs and i think as you never looked through anything better than the two you have mentioned and TBH everything else i have viewed through hasn't done it for me like those two do,I prefer refractors and low power viewing and have SW BD 100 and 80mm scopes which contrary to what some might think are more than worthy to use these eyepieces with in my book.
The Docter is like looking through an 88 deg ortho with 20mm ER and the Nikons perfectly flat sharp pinpoint stars across the whole FOV and satin black backdrop cannot be bettered but comes at a price and well worth it

[ausastronomer]

Hi Andrew,

The contrast in the 17mm Nikon NAV HW is something quite special, that I haven't seen any other eyepiece, with the possible exception of the Zeiss orthos, quite able to equal. The Docter gets very close as well. Of course the Zeiss orthos have short eye relief and a narrow FOV, so not quite a level playing field. To be able to achieve what they have achieved in a long eye relief wide field eyepiece is a credit to the Nikon Optical Engineers. In my 14" Zambuto powered SDM the Nikon is a stunning performer.

Unfortunately with the multitude of eyepieces I already own and enjoy I can't justify the cost, as I don't observe as often as I used to.

Cheers and enjoy
John B

[morls]

The 16mm Nagler arrived yesterday, and by luck the skies were clear! I only had a brief time to play last night, but all indications are that it'll work out well. The eye relief is fairly tight, but wasn't a problem. Time will tell, but I'm very happy so far.