2" 26mm / 30mm / 32mm / 40mm...DECISION SOS!!

[rob7]

The scopes.. Celestron C6sgt SCT @ F10 and a Revelation 12" dob @ F5.

By early next week I'll end up sitting pretty with four 2" eyepieces. Trouble is I don't know if I should keep them all [GREED], or keep 'one' or 'some' of them? The range I will have is;

2" REVELATION 26MM.

2" GSO 30MM.

2" MEADE SERIES 5000 32MM.

2" MEADE SERIES 5000 40MM.

Bearing in mind I have a mediocre understanding of the ups and downs of wide angle eyepieces in fast and slow scopes, but what I would like to acheive if possible is to be able to use the 2" ep's in both scopes to get good quality 'overall' widefield views of the sky Priority is the 12" dob, but In the C6 I would hope one or all of the 2" eyepieces would give me a better wide field view than a 1.25" 32mm I've already got in a Revelation set [i Know you can get focal reducers, but that's a pressie for another time]. Will I be able to find uses for all the 2" ep's or should I concentrate on a one or two? Obviously, if I sold on a ep or two that would free up some dosh for a reasonable planetary ep to add to my 'armoury'! But, money issues aside and sticking to science and experience, what do sgl members think they would do and why??

[Andrew*]

So you got the 32mm as well in the end?

My thoughts are thus:

Keep the 32mm and sell the rest. My reasoning:

- 40mm will give you a 8mm exit pupil in the dob, which might show up a dark patch in the middle of the view - your secondary mirror.

- 30mm - better in slower scopes, and too close to the 32mm

- 26mm - also too close to the 32mm.

- The 32mm is a great eyepiece, it will give you a 6-and-a-bit mm exit pupil (rather comfy) and it will show you a good amount of sky in both scopes.

HTH

Andrew

[rob7]

Hi Andrew. It's your fault I panic bought the 32mm as it was suppost to be his last one. I do actually plan on keeping the 32mm, with what I've read since, but the other eps I thought I'd pose the question to members for a broader view on any thoughts they might have.

Cheers, Rob

[Andrew*]

sorry :oops:

[rob7]

Panic buy is another word for 'greed'!

[rob7]

Any more points of view?

[James]

An f/5 scope is a fairly hard test for an eyepiece and the eyepieces will most likely perform differently from how they do in the SCT with the possibility that more aberrations will be visible. Its quite possible that after using them on the f/5 scope your mind will be made up for you! At the very least use compare the 32mm versus the 30mm and keep the better of the two if you want to free up aa little money.

Andrew's right of course about the large exit pupil that the 40mm eyepiece will give you but I've been able to use a 40mm Paragon in my scope (exit pupil 8.5mm) and I've been quite happy with the quality of view.

Whatever happens let us know what you decide!

James

[rob7]

Thanks James for your input. I would dearly like the 40mm to do a good job in either of the scopes as i've always had a vision it would provide wonderful views [rightly or wrongly...]. With you saying you get pleasing views with your 40mm, I shall be keeping my fingers crossed. Even before testing them altogether, if I ever get the chance, I'm leaning towards losing the GSO 30mm at least.

Regards, Rob.

[iancandler]

From personal experience with similar eyepieces and similar scopes, (10" f5 dob and C5 sct) I would just drop the 30mm unless its the ultra wide moonfish one or has M42 threads which you may find useful ofr eyepiece projection photography..

The 26mm GSO I found gave me really good views, especially of M42.

32mm is a nice size between 26mm and 40mm.

40mm is ideal for widefiled views.

[rob7]

Well I received my Series 5000 40mm yesterday and what a nice chunk of metal it is. The Rev's are nice but you can see and feel the quality of the Meades in comparison, [obviously priced accordingly]. Well, from what I'd heard/read regarding the problems I might have in my 12" F5 dob and 6" F10 schmitt, I thought I'd pop it in my dob to daylight test it. My worries proved unfounded. I got a tiny central obstruction shadow only if my eye wasn't in the right position. Other than that I was very happy and I thought I'd wait for nightfall to see how it performed. I waited for Orion to rise to a nice height then I had my first go at looking for M42. WOW, within seconds of putting the 40mm in the focuser I had found it. If nothing else its a fantastic finder, but to my untrained eyes the view through this eyepiece was super. It was great to see the contrast of M42 against a dark starry sky. There was a little distortion of stars to the edges and knowledgable Sgl members might find other issues what they wouldn't accept, etc, but I couldn't see em'! Tried the 40mm in my schmitt this afternoon and bearing in mind you have to keep your eye reasonably in the right place I was again smiiten with the terrestial view, [best daytime view I've eve had of any eyepieces I've owned!!!Looking at some birds in a distant tree was awesome. [very bright, clear and detailed. Its going to get a lot of use during the day on weekends away. Can't wait to give the 40mm a whirl in the schmitt tonight. At this moment I'm well chuffed and I can safely say this one's a keeps!!

[James]

The 40mm Meade Series 5000 is working just fine in my 10" f/4.7 scope. There are a lot less edge problems than I'd expected. They eyepiece itself is a bit of a beast though...

James

[rob7]

Yes, I'd agree it is a beast [large and heavy]. Had to rebalance my schmitt ota and fully tighten the diagonal, else I believe there could have been trouble!! 'No pain no again ',as they say...

[Andrew*]

knowledgable Sgl members might find other issues what they wouldn't accept, etc, but I couldn't see em'!

well that's what matters, isn't it! I say ignorance is bliss, and once you start looking for these problems, it's a slippery slope to the Naglers, Pentax's and the empty wallet!

I'm using the 20mm and the 32mm in my f/5 newt at the moment, and I find them great eyepieces.

Cheers

Andrew

[rob7]

Thanks Andrew for your earlier advice with the 32mm. I was on a budget to keep my better half happy, but now she's softened a little so I have a little more reign for astro goodies!!

[rob7]

Well to update, now I have all the eyepieces to compare and play with the decision ended up being pretty easy. Gone is the GSO 30mm which leaves me with the Rev' 26mm, Meade 32mm and 40mm. It was no contest in the end and the Meades in particular I think were always keepers, as the 40mm especially has give me some wonderful views nght and day in the F10 C6sgt. Last night the moon had emerged from the clouds and was high enough above the horizon for me to have a go at viewing it. The crescent shaped moon looked awesome in the 40mm, [the first time I've viewed it like a 3D globe 'floating in the sky and not a 2d disc]! The Rev' 26mm is still a great value eyepiece and that will help for the times I want to reign an object in a bit. So, if the wife don't mind...I don't mind and I'll remain reasonally greedy and give a home to 3 out of 4!!

Rob.