Which 7, 12 and 20mm eyepieces for an EdgeHD 8"?

[Zadoq]

Hi,

We are a couple of new comers to astronomy, so please bear with us and sorry about probably the noobish questions.

We have recently bought an Advanced VX EdgeHD 8" and managed despite quite poor viewing conditions to view Jupiter. It was our very first viewing and we were really excited about it.

We've already had some really good guidance from SGL. We nearly bought an eyepiece kit and then decided against it thanks to a post on SGL. Then I found some really good advice regarding which focal lengths I should get for the eyepiece at http://stargazerslounge.com/topic/43171-eyepieces-the-very-least-you-need/

Since during our first viewing of Jupiter, the planet appeared quite small (we used the 40mm eyepiece that came with the OTA, which gives 50x magnification), we thought we should be getting higher-magnification eyepieces. Using the post linked above, we figured out we need 7.5, 12.5 and 20 mm eyepieces.

We were initially naively thinking of sticking with the Celestron eyepieces, but then we thought we'd better ask people who have a lot more experience than we do.

So here it is: which eyepieces would you recommend for focal lengths of 7-7.5, 12-12.5 and 20mm? We would like something of good value, but of a quality that would match our OTA (an EdgeHD 8"). I don't know which brands are considered good and which are not.

Also, my partner had trouble with the eyepiece as she "kept on seeing black" from time to time. When I researched this, I think it might be due to the eye relief which stands at over 30mm (only found out about eye relief today )

Ideally she would like an eyepiece where she could make contact with a cup to avoid moving. My first reaction was that if there was contact, it would create vibrations and the impact of those would be a lot worse on viewing comfort than having to remain still in order to be aligned with the eyepiece axis.

What is the advice regarding eyepieces with cups? Do they exist (can't say I've come across yet)? If so, should they be avoided or is it sensible to use them?

Thanks

Nico

[Mr Spock]

For your scope the 7mm at x285 maybe a bit strong for regular use. Seeing conditions won't be that good too often.

I'd be looking at a 9mm (x222), 12mm (x167) and 25mm (x80). If you want celestron the X-Cel range is good. They have twist up eyecups so you can have a choice of up or down. The BST Explorer range is also a good match for your scope, though they only have an 8mm (x250) rather than 9mm.

[dweller25]

I would suggest just one eyepiece for your SCT - a zoom.

Baader do a good 8-24mm for £190.

Pentax do an even better 8-24mm at £405.

These eyepieces will give you a continuous range from x84 to x254

It's great not having to fumble around changing eyepieces and you can tune the magnification to the seeing conditions.

HTH

[Pig]

Hiya,

Your budget will be one of the deciding factors for choice of eyepieces.

I believe the HD are quality scopes and quite pricey so I would think you would want equal quality eyepieces  

The Pentax zoom mentioned in the post above has a great reputation and is a great option to start with (please note I have never used one)

Televue are also one of the best producers of top quality eyepieces and are my personal choice. The 10mm Delos would be an excellent start, in addition the Delos range have a clever feature that enables you to adjust the eye relief to suit. (this will help with the blackening you spoke of with your current eyepiece)

Both of the above makes also command a very good resale value should they not be to your taste.

[alan potts]

Having a scope with a long focal length, I agree 100% with the advice offered Mr Spock, its logical Jim

Alan

[earth titan]

I'd The Delos is out of your reach, then can suggest Televue Plossls. Although they may not give the same features as the Delos in terms of adjustable eye relief they are more realistic in terms of budget and still very good in terms of quality.

[michael.h.f.wilkinson]

At 20 to 24 mm the MaxVision 20 and 24 mm 68° are a steal at the moment.

[Dunkster]

The Edge HD scopes can make good use of quality eyepieces, so if you have the budget then something like a Televue 12mm or 14mm Delos or 13mm Nagler will last you a very long time, but there are less pricey options that will also do a great job - Pentax XF 12.5mm for example. This will be a good general magnification for globular clusters and planetary, although if you have good seeing where you are you might benefit from a higher magnification (9-10mm or so) for occasional planetary viewing.

Also, given you've paid the extra for the Edge HD scope, it'd be a good idea to get a nice wide field of view eyepiece... your current 40mm is a good place to start, but you can get other eyepieces of similar focal length that will show you more sky and make good use of that Edge HD corrected image  Baader Hyperion Aspheric, Explore Scientific 68, Televue Panoptic, Vixen LVW or a (TMB/TS) Paragon would all do the job nicely, or for a slightly more immersive experience one of the 82 degree designs from Televue / ES / Meade / etc. Choose a focal length carefully depending on how much sky glow you have where you are...if your current 40mm shows a nice black background between the stars then you're lucky

Personally, I find I get most use out of the 40mm end and the 12-14 (just the two!) and rarely anything in between, but ymmv...

[Zadoq]

Thank you all for your advice. For now, we have gone for the Pentax zoom mentioned above. I did like the fact that lens swapping wasn't required. We had our first view of Jupiter with it a few days ago and we were pleased with the result. An eyepiece with a wider field of view sounds appealing too, so no doubt I'll come back to this post when the Crhistmas and telescope buying financial pinch has gone.