C11 vs 12" Dob

Presently my largest scope is an 8" Dob. I'd like to gather a bit more light so I can see DSOs better. Can't make up my mind between a Celestron C11 ( I have a CGEM to put it on ) or an Orion 12" Truss Tube Dob Intelliscope.

I'd like to hear which scope you'd get if you could only get one.

Thanks,

Bob

Sell the 8" and get both!

My vote would be the 12" Dob. More aperture, less problems with dew, it still works if your battery is dead, and wider fields of view.

Then again, if you can spring for it, there is a 15" f4.5 Obsession for sale in Phoenix right now on A-mart at a great price!

Bob,

I would go with the C11 if I had a CGEM. There is a lot to be said concerning Push-To vs GO-To. In my experience 1 inch of aperture does not make much difference in scopes this size. There are many other factors to consider in your choice as well. Ease of setup. How often and how far are you going to have to transport the scope if at all? What are your favorite deep sky targets? This would determine how much field of view you need. Do you live in an area where dew might be a problem? How often are you willing to collimate you scope for best performance? Newtonians tend to go out of collimation more often then SCT's. I could go on but if I were you, I would write a list of things I want the telescope to do (observing and mechanical) and see which one fits the bill the best.

BTW, I did own a C11 and an Orion XT12g (recently) at the same time.

For what it's worth,

Keith

Hi Robert,

I've had, made, used scopes from 50mm to 29". Of them all, my 17.5-inch Dob was the best value for deep sky. These were all in domes, so transport was not an issue. Provided visual deep sky is your goal, the simple Newt Dob is best. For portability, I would recommend 8" Dob or bigger. Orion is good value. I notice many truss Dobs are way deficient on stray light baffling. You can see WAY more contrast if you use a dark shroud and extension up beyond the secondary. I use the 29 and a Meade 14 now - but must admit they are too big. Even in domes on my own property they are still a hassle to use. Of course I still want bigger ones - resist this mental illness... Tom Dey

Robert Alba said:

Presently my largest scope is an 8" Dob. I'd like to gather a bit more light so I can see DSOs better. Can't make up my mind between a Celestron C11 ( I have a CGEM to put it on ) or an Orion 12" Truss Tube Dob Intelliscope.

I'd like to hear which scope you'd get if you could only get one.

Thanks,

Bob

Bob:

I would get neither since I already have a nice 12.5 inch Dob..

These scopes are pretty close, you get more punch with the larger Newtonian but not a great deal more and the C-11 is still reasonably portable. If you like low power "richest field" viewing, the Fast Newtonian is definitely the way to go...

The advantages of a truss Dob over an SCT increase as aperture increases, these days a 11 or 12 inch scope is still mid sized.... If you want a 16 inch, about the only way to go is a truss Dob.

Jon

Bob,

Was at a star party last night and a lady had one of the Celestron Goto's, not sure which variant.

Pin sharp optics. Very quit goto's and near silent tracking.

She was with a group, and they would all take turns looking through the scope at fairly high powers. This would have been hard without tracking, as normally there would be a fair amount of adjustment to re-center the view in a dob, (as you know)

Something to be said for tracking.

For dso's I would go with the dob.
#1 you will have a wider field of view with the dob,
f4.7 vs f10

#2 with dso's, usually low power is the norm so
to me tracking is not as big as if high power planetary
was the goal.

#3 the dob will cool down faster.

I have owned both 12 dobs and c11's,
don't get me wrong I think the c11's are great scopes
I just hate eq mounts, and heavy ones at that.