Why shouldn't I go 2" on 8" edge?

[dreamlander]

I will be buying my first telescope and have decided on the 8" edge hd. I know what you are going to say, "just get out and do some viewing before you start worrying about this eyepiece stuff." But I generally like to do a lot of research before purchasing things. I don't want to end up with a handful of 1.25" ep's and a powermate only to have buyers remorse wishing I would have gone 2" from the get go. It seems the upgrade would be worth it from what I read. It looks like it will cost about $230 for a Baader click lock back and a quality diagonal. So besides the cost to switch over why shouldn't I go for it? I can't seem to find any reason not to except I suppose using the .7 focal reducer would require putting the original back on.

Am I missing something else? or is it this simple?

thanks

[michael.h.f.wilkinson]

I put a 2" visual back on my trusty C8 and it is one of the best additions I have made to the scope. Go for it I would say.

[CodnorPaul]

+1 for 2" on a c8

[seo]

The backfocus distance (133.35mm for your EdgeHD) from the telescopes rear cell is the same with the backfocus from the reducer (if you measure from the reducer). That's not only what Celestron says but is also tested (at least in my EdgeHD 14").

For the 2" visual back as Michael said, go for it. Of course there has always been lots of discussions about the 1.25" and 2" EPs real optic/visual difference but this story starts always at the end of the visual back not at its beginning...  so again IMHO go for it and get a good one. If you put a 2" one you're not going to reduce the incoming light from the pre-installed flattener to your visual back even before it can reach your optics. From that point and on if you're going to buy/put   2" (not 1.25" with a 2" adapter) or 1.25" EPs in your 2" visual back in my opinion doesn't have any significant visual impact. Only the quality, the exit pupil (matching  the eyepiece exit pupil to the type of observing you want to do) and the true FOV compared to the AFOV of each one may play a significant role to that. 

[seo]

 That's not only what Celestron says but is also tested (at least in my EdgeHD 14"

Just to clarify, I mean tested with the proper Celestron EdgeHd reducer on my EdgeHD 14" which has a different back focus distance and it's the same with my Celestron reducer on/off. 

[PeterCPC]

i use a Baader 2" clicklock on the back of my C9.25 and I would not go back to the 1.25" visual back.

Peter

[michael.h.f.wilkinson]

Mine BTW is the regular Baader, not the fancy click-lock. Had that been available at the time, I would probably have got that. Now I will stick with the one I have.

[Chris]

I would definately go for 2" eyepieces. I had the C8 Edge plus a set of 2" ES100 degree eyepieces which was a great combination.

I didn't get on well when I tried to use the 0.7 reducer with eyepieces, I basically didn't find it secure enough. The diagonal would swing 180 degrees and hang pointing down when the mount slewed, I soon gave up on that idea.

[TheUKDave]

Hi Dreamlander, I'm a newbie myself, and a fellow researcher  

I've only recently bought my first scope, which came with a 2" diagonal, and I don't imagine how I'd cope with only 1.25" eyepieces.  And bearing in mind that my scopes focal length is less than half of the one you're looking at, you'd be very limited indeed in true field of view with 1.25" eyepieces.

Infact, with 1.25" eyepieces, I think you'll be limited to around 0.77° of TFOV, with 2" it would be more like 1.3°.  I personally spend a lot of time viewing clusters with around 1.5-2° TFOV, so as I say, I'd definitely want the larger option.

To answer your actual question, I don't see any disadvantage other than cost, and potentially the size/weight/cost of the larger eyepieces that you'll also then be buying!

Cheers,

Dave