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pneuman
05-09-2008, 09:15 PM
Hi guys,

I recently picked up a 21mm Stratus for my 8" f/6 dob, and it's great for low-power work, but I'm now looking at getting a quality mid-to-high-power eyepiece to replace the GSO Plossls that came with the 'scope. I need something that's good at planetary work, and preferably something that can also give good contrasty views of smaller DSOs from my suburban backyard.

Does anyone have any recommendations? I'm looking at the T6 Naglers at the moment (maybe a 9mm or 13mm), mainly so I can get high magnification without having to nudge the dob every five seconds, though this soon in to the hobby I'm a little hesitant to pay nearly $350 for one eyepiece. Are they really worth it? Do they Barlow well? Any other options I should consider?

koputai
05-09-2008, 09:29 PM
Hi Leigh,
I have the same scope, and have both the 9 and 13mm T6 Naglers. They are both excellent eyepieces in that scope, and if you can stretch that far, are far better value than any of the cheaper ones I've tried. That's the problem with lesser eyepieces, you buy every single one of them trying to get something godd, and end up buying a premium eyepiece in the long run anyhow!
The 13mm Nag gives the most crisp, beautiful views, but if it's higher mag you want, the 9mm Nag is superb, and is definitely my favourite eyepiece in the 8 inch Dob.

Cheers,
Jason.

acropolite
05-09-2008, 09:34 PM
I seem to remember seeing an 8mm Meade Series 4000 UWA (http://www.iceinspace.com.au/forum/showthread.php?t=34362) in the Icetrade area, for a bargain price, it may be worth looking although I fear h0ughy may have already snapped it up.

JethroB76
05-09-2008, 10:00 PM
Although it appears you are after big AFOV, the Pentax XF 8.5 and 12 mm (60 degree) are excellent optically, very light and compact.. you can find them for <$200 each if you're willing to look at importing from Japan...

wavelandscott
06-09-2008, 09:18 AM
I'd strongly encourage saving enough money to buy a premium widefield eyepiece...in the end you will be ahead (in my opinion).

Not only will you get the benefit of the wide field and high quality optics but if you ever decide to sell it you are more likely to get a higher percentage of your purchase price back (of course depending on currency exchange rate)..just shoot for an exit pupil of 2 and you will be in business.

I have currently or have owned the following in and around the focal length that you are looking at...

13 mm T6 Nagler
11 mm T6 Nagler
10 mm Pentax XW
7 mm Pentax XW

The 11 mm T6 Nagler was my first premium eyepiece and it worked a treat in my 8 inch reflector dob...I really liked it a lot.

Through a long chain of events and the aquisition of some other scopes I got the Pentax XWs...I then traded the 11 mm Nagler for the 13 mm Nagler. The 11 and 10 were just too close together and the Pentax just edged out the Nagler for the purposes I intend to use it for...but it was a close hard decision and I do miss the 11 T6 although it would not have seen much use and the 13 fit my line-up better...

I would gladly/proudly recommend any of the above.

Good Luck and Clear Dark Skies to you!

pneuman
06-09-2008, 12:31 PM
Thanks for the feedback guys! I think the 13mm Nagler, with a 2.2mm exit pupil and 92X magnification might be the way to go. Will that work well with my 2X Barlow for planetary viewing?

koputai
06-09-2008, 04:49 PM
In that same scope/EP combo, I use a Televue 2x Barlow (1.25") and the result is very good (for a Barlow - don't really like 'em myself).

Cheers,
Jason.

xstream
06-09-2008, 05:10 PM
Just to throw a spanner in the works the 12mm T4 Nagler is well worth considering, you have the added benefit of the instadjust eye relief with all T4's.

pneuman
08-09-2008, 08:41 PM
Well, I took the plunge and picked up the 13mm T6 Nagler. Just have to wait for a clear night now to give it a go! Thanks again for all the feedback.

I'm sure I'll want a smaller focal length eyepiece later on, for nice planetary views without needing to barlow (maybe the 8.5mm XF, or a Radian perhaps?), but I'm sure I'll be very happy with the Nagler, and I'm also sure we could all name just one more thing we need :)

wavelandscott
08-09-2008, 11:05 PM
Congratulations! I hope that you get many clear dark nights to enjoy your new eyepiece!