Worth getting help from a little higher power?

[Dunkster]

Folks,

Given the opposition of the lord of the rings coming up soon, I don't want to miss out given the limited viewing opportunities we might have from our cloudy friends. Had a good view of Mars the other week it would seem, and on the understanding that those conditions come up few and far apart I can't help wondering what it might have been with a little extra...

I know the golden rule and all that, 50x per inch, don't bother with >200x in the UK.... so with the 6SE and Mak both FL=1500mm and my shortest FL EP is currently my 8.8mm ES82 (170x). That leaves me somewhere in the region of 200 - 300x that I'm lacking.

For those extra-special planetary moments, is it worth getting a shorter FL? More concerned about opportunity than money in this regard, and while the sale has ended, a 6.7mm ES82 is only US$120... 224x can't hurt that much can it

Or is it worth having one in my arsenal with an even shorter FL? Give it another year or so and I might get a goto dob, so I don't think it'll be totally wasted...

Thoughts? (as always, hugely appreciated!)

[rory]

what about a good barlow instead ?

[John]

As long as you don't mind spending some £'s on an eyepiece / eyepieces that won't see a lot of use then it's good to have the option.

I have a 3.5mm Nagler that gives 257x with my ED120 refractor. It's actually proving more useful than I thought it would with both Mars, Saturn, some tight binary stars and the Moon having shown well on a couple of nights of decent seeing.

I did have the 2.5mm Nagler a while back but that really was too much and the ultra small exit pupil showed up too many "floaters" in my eye for my liking so that one was sold on.

[Ags]

I use 220x with my 102mm mak all the time. It is my default EP for Mars and Saturn. Useful for the moon too on some nights. Also ideal for splitting tight doubles. Go for it!

[Dunkster]

Thanks chaps, so I'm basically looking for a 6mm or thereabouts, or multiple thereof. I've read a lot of positive about the powermate, worth having in the box too? It's only money

On the EP side, given that I wear specs (not normally for viewing, but...) so shopping list of potentials are...

• ES82 6.7mm 224x (parfocal with 8.8/11)
  
• TV Nagler 7T6 214x
  
• TV Delos 6mm 250x
  
• TV Radian 6mm 250x
  
• Pentax XW 7mm 214x
  

I've also got my beady on a power mate, as I'd like to do some planetary/lunar snapography... probably the 2.5x. In which case, maybe an ES82 14mm or Nagler 13T6? Can't seem to find much in a 15mm

Any good 'uns I've missed? Like the sound of a BGO (contrast), but there are times when I need to use my specs (entertaining OH, friends, family... given how much I spend, I have to spread the joy around a bit LOL)

I figure it's diminishing returns... the higher power and cost... ES82 6.7mm and 6mm Radian worth while for under $400? I'll probably regret it later, but I want to eek the best I can

[John]

My 6mm is an Ethos which is quite superb but quite a few more £'s than anything on your list. My 5mm is a Pentax XW and I'm really impressed with that too - no reason to suspect that the 7mm isn't a cracking eyepiece either. I've owned the Nagler T6's in the 13mm - 2.5mm focal lengths and liked them a lot but their eye relief is tighter than the Pentax XW's. The UWAN / Nirvana's are excellent too and a lot less £'s than Naglers.

A Powermate might be a good option as they do seem to add only the magnification. Depends whether you want another optical device to fit in the dark I guess.

[Ags]

Maybe before you spend £££ just get a TS Planetary HR or similar TMB clone at 6mm? See if the focal length works for you before you spend a lot?

Also consider the Speer WALER 5-8mm zoom - highly respected from all I hear but now (recently) out of production?

[Dunkster]

As much as I might want an Ethos, it's something I'd want to see for myself before plumping down... I'm not yet convinced I can see all 82 degrees of my ES82, maybe there's a technique I'm missing!

SW sounds interesting - on Antares' website they've got SWA2 listed, wonder if they'll produce a new version? A decent quality zoom for 5-8mm sounds like a great idea

[RikM]

I can confirm that the 7mm Pentax XW is a great eyepiece.

[John]

As much as I might want an Ethos, it's something I'd want to see for myself before plumping down... I'm not yet convinced I can see all 82 degrees of my ES82, maybe there's a technique I'm missing!...

There is so much more to an Ethos than it's extra wide field. The contrast and sharpness they deliver rivals specialised planetary eyepieces - I've tried the Ethos against some of the very best and have witnessed this for myself.

Also one of the main points of ultra wide angle eyepieces is not to be able to see the edges of the field of view in my opinion. I love the "boundless sea of stars" concept

Plus, with undriven scopes like I use the drift time of objects is longer with the ultra wides.

I appreciate that not everyone likes these features though, the cost is not insignificant and some of the narrower field alternatives are very good too

[michael.h.f.wilkinson]

First of all, there are certainly occasions when you can go beyond 200x (I regularly use my Pentax XF 8.5mm (239x) and recently used my Nagler 12T4 with Meade TeleXtender 2x to get 338x on Mars. I am aiming to get a Pentax XW 7 for 290x. Maybe I will even get a Delos 6mm for 338x.

I my self decided not to go the Ethos way, simply for reasons of eye relief: 15mm is uncomfortably short for me (I wear glasses while observing), which is why I replaced my Meade UWA 14mm with a Nagler 12T4. Also, for planetary observing, a large FOV is not that necessary (unless your scope does not track). The Delos sounds great with 72 deg and Ethos-like (or Pentax XW-like) sharpness, contrast and transmission.

[Dunkster]

Yes indeed, if the Delos really is up to the standards or the Ethos just with narrower FOV, then that may well be a treat!

As always, thanks for helping me see the light, literally

[RikM]

I have been fortunate enough to compare a 10mm Pentax XW to a 10mm Delos tonight.

I only had an hour tonight but first impressions are that the Delos is marginally sharper but the Pentax gives a marginally brighter image. There is almost nothing in it and a couple of times I lost track of which one I was actually looking through.

[michael.h.f.wilkinson]

I have been fortunate enough to compare a 10mm Pentax XW to a 10mm Delos tonight.

I only had an hour tonight but first impressions are that the Delos is marginally sharper but the Pentax gives a marginally brighter image. There is almost nothing in it and a couple of times I lost track of which one I was actually looking through.

Thanks for that. I am pondering which one I would like to get, and on planets I would choose sharpness over transmission, in general. In fast scopes, where 10mm is more of a planetary nebula EP, I would suggest transmission is more important than sharpness. The Delos is (still) somewhat cheaper, so on balance I would go for that.

[RikM]

Thanks for that. I am pondering which one I would like to get, and on planets I would choose sharpness over transmission, in general. In fast scopes, where 10mm is more of a planetary nebula EP, I would suggest transmission is more important than sharpness. The Delos is (still) somewhat cheaper, so on balance I would go for that.

I agree I was using these in an f/4.7 Dob and 10mm is my normal planetary neb / galaxy eyepiece. The Pentax was definitely brighter and would be my choice for DSO. I compared them observing M81, M82 and the other one in the same area whose designation excapes me atm, the Eskimo neb as well. Mars and Saturn were more of a puzzle. Mars was definitely clearer in the Delos but Saturn (on the whole) was marginally better in the Pentax. I've gone over it again and the rings / ring shadow and Cassini division were more easily visible with the Pentax even though the disc was resolved more cleanly with the Delos.

Need to spend a bit more time with these two EP's over a few nights to get a true comparison really. Like I said I only got an hour in. It could also be that the Pentax is mine so I am familiar with it, while the Delos is on loan for a little while.

[michael.h.f.wilkinson]

I assume you picked up NGC 3077, which is near M81 & M82. To complicate matters, I have a slow SCT and a fairly fast APO (F/6). I will most likely be traveling to Japan in the fall, so might be able to pick up an XW cheaply. The 7mm would be my first choice, as I already have a Radian 10, which is a very good EP indeed. The Delos 6 focal lenght is already covered by 12T4 + 2x telextender, and anyway, it is a rare for me to use that. I tended to use the Vixen LV7 I used to have quite a bit, and the 14mm UWA + TeleXtender 2x also got quite some use.

[rwilkey]

Just to throw a spanner in the works, I have a 7mm Axiom LX, 82 degrees and it is superb for planets and splitting doubles, good eye relief too, you might consider one of these. I also have a SW SWA 3.5mm which unfortunately has not had much use, too much power, but I love my Ax.

[michael.h.f.wilkinson]

Just to throw a spanner in the works, I have a 7mm Axiom LX, 82 degrees and it is superb for planets and splitting doubles, good eye relief too, you might consider one of these. I also have a SW SWA 3.5mm which unfortunately has not had much use, too much power, but I love my Ax.

The Axiom LX may well be good optically (and has had some good reviews, I have seen), but for me 13mm eye relief is not enough. Anything below 16-17mm causes my glasses to occasionally knock into the EP, causing vibrations which ruin the image. For those without the need to wear glasses while observing, 13mm is fine!

[E621Keith]

I assume you picked up NGC 3077, which is near M81 & M82. To complicate matters, I have a slow SCT and a fairly fast APO (F/6). I will most likely be traveling to Japan in the fall, so might be able to pick up an XW cheaply. The 7mm would be my first choice, as I already have a Radian 10, which is a very good EP indeed. The Delos 6 focal lenght is already covered by 12T4 + 2x telextender, and anyway, it is a rare for me to use that. I tended to use the Vixen LV7 I used to have quite a bit, and the 14mm UWA + TeleXtender 2x also got quite some use.

If you are going to Japan, may be you should consider the Nikon NAV SW as well.

[michael.h.f.wilkinson]

If you are going to Japan, may be you should consider the Nikon NAV SW as well.

Thanks for the tip, I will check them out.

[cs1cjc]

ES82 6.7mm sounds fine to me, though if you are not going to use that focal length very often, then a 1.5x barlow might do the job. I am currently using the screw-in 1.5x GSO barlow for the few occasions when I want a something between my ES82 8.8mm and 4.7mm.

[Moonshane]

One eyepiece not mentioned is a Nagler 6-3mm zoom. these used are about £200. this may sound a lot but it covers the whole range with infinite positions so can be tuned for the seeing conditions. I use this with my 1600 FL 6" newt and was using it the other night on Mars at about 300x with my 16" newt masked to 6.7" with a focal length of 1840mm.

I use it on the moon a lot and it's also great on double stars.

I also have 7mm, 9mm and 12.5mm BGOs and these really are excellent for the money but certainly with a lot less field.

[Dunkster]

Fantastic chaps, thanks - decisions decisions...

[Dunkster]

So I pulled the trigger on a 2.5x Powermate.... I figured that would give me a spread of extra crazy FL with my current ES82 and in combination with a 14 or 15mm EP to come, but also get me on the ladder of planetary imaging.

Haven't decided whether or not to go for 14mm ES82 or Pentax XW, or 15mm Luminos

[Dunkster]

I'm sure it would have worked out cheaper if I'd bought them here... the temptation was just too much!

I picked up a TMB Planetary II in a 6mm but couldn't get hold of an ES82 6.7 anywhere, so ended up with a completely impractical Meade UWA 5.5. I got a good deal, so if I get one good view of each of the planets through it I'll be happy

I guess that leaves me with a spare Powermate Now I really will have to put that webcam to use or I'll get nagged for throwing money down the toilet.....