Newbie help

[Jtrohe]

I recently purchased: (photos attached)

8se 8" Celestron 

Meade 2in diagonal

Celestron focal reducer

 

I want to view planets, nebula, etc in Cleveland Ohio area.

 

What advice would you give me in regards to either keeping or returning the diagonal/reducer? If keeping either or both, what eye pieces would you recommend starting with (I only have the 1.25 eyepiece that came with the telescope)? Are there any other important pieces of equipment I should buy other than eyepieces? 

Thank you so much for any help/advice. If you could explain why you make recommendations so I can understand and learn, that would be much appreciated also!

[Floater]

You’re good to go with what you have. Spend some time using the kit you have before looking to add anything. I know this will go against your enthusiasm which is driving you for ‘more and better’ but it is good advice. 🙂

[Cosmic Geoff]

I would not have bought the 2" diagonal or the reducer - I still do not own either for my C8 SE.  Whether you keep them is up to you.

You will probably want some more eyepieces, e.g a 15mm Plossl and an 8mm or 10mm eyepiece, to get some more magnification (useful on planets).

[Jtrohe]

Because the eyepiece that came with the scope is just 1.25, should I get a 2in eyepiece?

[Floater]

56 minutes ago, Jtrohe said:

Because the eyepiece that came with the scope is just 1.25, should I get a 2in eyepiece?

No. Almost certain that there is an adapter in the diagonal.

[Cosmic Geoff]

10 hours ago, Jtrohe said:

Because the eyepiece that came with the scope is just 1.25, should I get a 2in eyepiece?

Why?

The only reason for going to the 2" format is that it allows you to use low-powered eyepieces with adequate field, ie lower power than 32mm, in the quest for wide field views. My lack of enthusiasm for this approach stems from the prospect that because of the construction of the SCT, with a hole of about one and a half inches in diameter through the primary mirror, there will be some vignetting, and once you buy a 2" visual back, 2" diagonal and 2" eyepiece, the resultant expense could have bought you a widefield telescope that might do the job better. 

If bright widefield views are a priority, consider getting an 8" F5 Newtonian. I used to have one, and it gave a superb view of the double cluster in Perseus - both in view at the same time.

If you already have a 2" diagonal etc, you may as well get a low-power 2" eyepiece as well, but don't expect it to be as cheap as a 1.25".

[Jtrohe]

I was under the understanding a 2"eyepiece makes viewing more comfortable. I had read that there is more relief and less eye strain. If the consensus is that a 2in isn't worth it, I will probably return before I try it out.

[vlaiv]

8 minutes ago, Jtrohe said:

I was under the understanding a 2"eyepiece makes viewing more comfortable. I had read that there is more relief and less eye strain. If the consensus is that a 2in isn't worth it, I will probably return before I try it out.

Two reasons to use 2" eyepieces:

- first and most important - certain combinations of focal lengths and apparent fields of view simply can't be made in 1.25" format. Longer the focal length and wider the AFOV of eyepiece - larger field stop it needs to have. Maximum field stop in 1.25" eyepiece is dictated by barrel size - which is 1.25" or roughly 31.5mm. You need at least 1mm for barrel walls and filter tread and such and it leaves only something like 27-28mm for field stop.

If eyepiece design requires larger field stop - there simply is no option but to go for 2" eyepiece (in fact 2" also has the same limit and there are even 3" accessories - but are rare - usually observatory class gear for very large scopes).

- some people prefer 2" format because if feels more secure in 2" diagonal - better clamping for heavy eyepieces. This is the reason some 1.25" eyepieces have 2" adapter that can be screwed on (look Baader Morpheus range or their zoom).

 

Fact that 2" eyepieces have larger eye relief is not related to the fact they are 2" eyepieces - but rather to the thing that makes them 2" eyepieces - focal length and design. There are plenty of 1.25" eyepieces that are long eye relief and comfortable - take 32mm plossl for example (this is by the way - about the max field stop in 1.25" eyepiece - 32mm combined with 50 degrees AFOV).

[joe aguiar]

I would say keep the 2" diagonal I havethem in pretty much every scope I own when my skywatcher 80mm apo. Sure using a 1.25" ep is low power BUT a 2" low power is even lower. 

If you ever are at DARK country skies having a really low power and scanning the milky way is amazing.

BUT also your 8"sct is 2000 mm focal length that that's kinda long. There will be a lot items you wont be able to see or at the very least see half.

so even a 1.25" 32mm ep plossl is 63x power/ 2000 divide by 32mm. that's not high power BUT also not low.

you could benefit from a 2 ich 40mm ep or 2 inch 45mm ep MAX would be a 50

this will also give a larger true field of view compared to an 1.25"and make trying to find stuff easier AND you can still use all your 1.25" ep with it too

I prob would return the focal redicser tho have the 2" diagonal and low power 2inch ep will do the same and u don't need both items.

joejaguar