Delos v Panoptic v Nagler

[osbourne one-nil]

Loving my new 8" Portaball and it's working really well with my 24mm Panoptic; a great combination. For my mid-power eyepiece I've got a 15mm Panoptic, which they no longer make. It works great, although eye relief is a bit mean. For high power, I've currently got a 6mm Delos. It only just works in the Portaball and is certainly too heavy low down, when viewing things like Saturn and Jupiter at the moment. Also, it provides x250 in the 1500mm scope which I reckon is unrealistic most of the time, particularly here in Cumbria. So I'm wondering if something like a 7mm or 9mm Nagler would be better. Either would certainly be lighter, but are there any drawbacks, because on paper it looks a no-brainer; wider FOV and lighter weight, but then I wonder why I went for the Delos in the first place. I don't wear glasses btw. 

Also, could there be something better out there than the 15mm Panoptic?

Much obliged.

[John]

The Delos is just about the finest wide field eyepiece around at the moment. Thats probably why you went for it 

With the sort of optics that the Portaball has I'd have thought 250x would be a very usable magnification - top quality optics seem to support high magnifications with some aplomb. 

Pity you can't counterbalance the scope in some way to enable the Delos to be used. I doubt you will find a finer eyepiece to be honest.

The T6 Nagler is a very decent compromise and it's quite a bit lighter but the 12mm of eye relief might seem constrained compared with the Delos and I think the light transmission and sharpness of the Delos would be slightly better.

[osbourne one-nil]

Thanks John, maybe it's a keeper then seeing as it works beautifully in my TV85. Interestingly, last night, the Delos didn't actually cause any problems balance-wise, but I did feel it would go at any moment. There must be a way to make it work - time for a good Google.

[John]

I find that the need for counterbalancing increases as the elevation of the scope decreases. Ideally the counterbalancing would gradually increase as the scope is pointed lower. Once way of doing this that used to be popular, if a little crude, was to hang a length of chain on the back end of the scope. As the scope dips, more chain lifts off the ground and the counterbalancing effect increases. Raise the elevation of the scope and the opposite occurs. I seem to recall something similar being done with bungees too. Whether something like that could be applied to the Portaball without spoiling it's elegant lines I'm not sure.

[scarp15]

I use a 10mm delos and 9mm, 7mm T6 nagler. Each in their own way is superb dependent on the subject being observed. However I would not hesitate to include another delos, the 10mm has been very satisfying on a variety of targets. In some ways it may be useful to keep with a particular line of e.p's, enabling your eye to become accustomed and to settle more. The T6's are indeed very light and compact, however I now use mine with a Televue Equalizer, so as to effect balance with heavier 2" e.p's and therefore retain the target in the field of view. My own scope though is fairly bottom heavy and so does not have any particular balance issues at low horizon points and the tension brake assists to.

[Moonshane]

this http://www.cloudynights.com/documents/portaball.pdf has some suggestions re adjusting the fluidity of the motion

if you don't need long eye relief or wider fields then plossls and orthos would be light and give good results at higher powers. if you do prefer the wider fields, I agree the T6 Naglers are excellent although I have only used one and for a short period

[AlexB67]

I thought of a sliding dovetail attachment as a counter weight on my Dob may be a nice mod one day, If that makes any sense. It would give smooth fine tuning ability, a sliding weight that can go up and down the tube, in similar way some of the mount attachments  work. On the Heritage 130p you can slide the OTA up and down, so the reverse idea, the tube stays fixed, but the weight does the sliding instead to give fine tuning balance.

Not so straight forward to attach with the truss design portaball, but no doubt something could be made/designed if you have the tools.

[alan potts]

Between 6mm and 10mm I have a reasonable selection of Televue eyepieces which account for the Delos, Nagler and Ethos ranges. With 6mm D at the shorter end followed by the 7mm  & 9mm Naglers, apart from a tiny bit better contrast ( and I do mean tiny) and the same with scatter there is not much in it. The Nagler range do have a degree of pincushion too but this is part of the design and not on their own in having this.

Ethos (6mm, 8mm and 10mm) are as far as I can see as good as Delos, apart from the price tag and larger FOV.  I firmly believe that Naglers seem to have lost a bit of favour with many since the Delos fuller range has landed . Don't overlook the Nagler they are very fine eyepieces that can be aquired S/H cheaper in most cases than the Delos, its only the longer ones that are more expensive and there really is little between them.

Alan

[osbourne one-nil]

Thanks for the link the the CN review - I'd not seen that one before. I've wondered about placing some weight in the base, like described there. It wouldn't take much and I'll never be able to use something truly heavy like my 35mm Panoptic as it's only a 1.25" focuser, so I'll have a think. It would mean taking the mirror out, which I don't imagine wouldn't be too difficult and I have been wondering about cleaning the mirror, but it's no worse than the one in the review and I am a bit in awe of the Zambutto mirror so might opt to leave well alone as long as possible!

I suppose I could try something sliding up and down the truss poles?

Can't see I'd gain much from trading in the Delos for a Nagler - perhaps best to save my money.

[great_bear]

For high power, I've currently got a 6mm Delos. It only just works in the Portaball and is certainly too heavy low down, when viewing things like Saturn and Jupiter at the moment. Also, it provides x250 in the 1500mm scope which I reckon is unrealistic most of the time, particularly here in Cumbria.

It will work fine, but you do need to wait for both the telescope and the planet that it's sitting on to cool down - particularly at this time of year. Even in winter I have to wait until 1am for the best planetary views.

Most importantly, you need to check the jetstream forecast for a given evening before you shoot for upwards of 150x or you can get a bad impression of the capabilities of your scope.