New scope

[neil groves]

Sometime in the new year I will be buying a new scope, I have a SW120ED currently and am pleased with it, my main interest is wide field and deep sky, I'm not really a planetary person, I just occasionally peek at Jupiter and Saturn so I don't need extreme power so I looked at Dobsonians and noted they are the light buckets of the Astronomy world, but also noted long exposure astrophotography can't be done with them, so I then looked at Celestron 8" but can only find them sold with a mount, I already have a mount so just need an OTA, I see some costing thousands which I don't have, what are good options for around $1000 please?

Neil.

[nightfisher]

some thing like an ED80 would be a great scope if you dont want a dob

[Dave In Vermont]

Try OPT in Oceanside, CA. They have OTA's of both Meade and Celestron 8" SCT's:

http://www.optcorp.com/telescopes/cassegrain-telescopes.html?p=2

And others are there as well. I've dealt with OPT for quite a few years, and will continue to do so. Excellent service and very knowledgable staff.

Clear and Dark Skies,

Dave

[MattJenko]

Seeing as you already have a refractor for some wider field shots, how about an RC for deep sky, something like : https://www.astronomics.com/8-f8-ritchey-chrtien-astrograph-steel-tube_p20071.aspx

(although rereading your post it seems this is for visual?)

Matt

[ronin]

If the scope is to be used for imaging then the Meade/Celestron range of SCT's are not really suited, the focal length is too long - the longer the focal length the more tracking errors are "magnified". Putting a reducer on to get one the same f number as the refrator is seems a bit pointless - just use the ED.

Really for astrophotography the route is more like a good fast apo refractor - as in an f/5-f/6 triplet - then use the 120ED for visual.

If the ideaa is to continue with the 120ED for imaging and you want a visual scope then yes an SCT will be good - the post is a little ambiguous.

[Dave In Vermont]

I have a Meade 12-inch LX90ACF, and it's outfitted for video-astrophotography. And there are some excellent focal-reducers available which, used properly, work very well to lend these SCT's quite well-suited for AP:

http://www.mallincam.net/uploads/2/6/9/1/26913006/focal_reduction_for_dummies.pdf

Though written with video in mind, this article is quite useful for other applications as well.

Clear Skies,

Dave

[happy-kat]

As you already have the mount what is it as this might help with the replies you get?

A dobsonian is a style I of mount on which the telescope, a reflector sits.

The astrophotography limit is the dobsonian mount and not so much the telescope potentially.

[neil groves]

sorry, yes my post left a little to be desired lol....I am going to use the ED120 for imaging and was looking for a larger aperture for visual.....glob clusters and open clusters in particular.

thinking about it though would a faster scope be better for imaging? mine is f7.5, would I get much advantage from say the WO zenithstar 71 at f5.9?....my main concern right now is light collection for visual but would a larger aperture be enough of an advantage to consider a larger scope for both imaging AND visual?

Neil.

[neil groves]

^{I am using a CGEM mount and maybe I could mount a WO zenithstar 71 piggyback on the 120ED if a faster aperture is going to benefit me more? then just get a big ole DOB for visual, something like a 8-10"? in fact a long focal length would give me better views of the planets even though i'm not an avid planet guy?}

^Neil.

[rowan46]

There isn't a scope for imaging and visual dso unless you have a high end and large mount If you are going to use the 120 for imaging it may be more cost effective to get a largish dob for visual it also gives you something to do whilst collecting photons. a thought just struck me isn't it odd that people are prepared to fork out for a dedicated imaging scope but not for a visual scope?

[rowan46]

^{I am using a CGEM mount and maybe I could mount a WO zenithstar 71 piggyback on the 120ED if a faster aperture is going to benefit me more? then just get a big ole DOB for visual, something like a 8-10"? in fact a long focal length would give me better views of the planets even though i'm not an avid planet guy?}

^Neil.

That sounds like a better plan to me your 120 would be good on planets  a fast refractor for imaging and a dob for dso's

[Billy Bluelight]

I have the Celestron Advanced VX 8 Edge HD but you could buy just the scope.  It has features that make it very good for astro-imaging and by using them you can reduce the F number significantly down to reduce exposure times.  Very nice optics an a lovely scope to use anyway but I bought it to be fairly future proof

[Dave In Vermont]

If you wish for aperture AND being fast:

http://www.telescope.com/Telescopes/Reflector-Telescopes/Reflector-Telescopes-for-Astrophotography/Orion-8-f39-Newtonian-Astrograph-Reflector-Telescope/pc/1/c/11/sc/344/p/101450.uts?refineByCategoryId=344

http://www.telescope.com/Telescopes/Reflector-Telescopes/Reflector-Telescopes-for-Astrophotography/Orion-10-f39-Newtonian-Astrograph-Reflector-Telescope/pc/1/c/11/sc/344/p/99602.uts?refineByCategoryId=344

I have an older 200mm F/4 of this type. Excellent optics. Being very 'fast' collimation is vital. So factor this in as well.

Clear Skies,

Dave

[neil groves]

Dave, will one of these enable me to attach the above 10" to my CGEM mount?

http://www.telescope.com/13-Orion-Dovetail-Mounting-Plate/p/7385.uts

Neil.

[Dave In Vermont]

At 25.5lbs, it would. Add to the weight of the OTA  some form of rings and mounting-plate - and you'll still be fine. The Celestron CGEM has a stated capacity of 40lbs, and it's always best to be well under this, and add a camera - you should be okay.

Perhaps someone out there who has more hands-on experience with this mount and it's abilities will arrive with a more definitive reply.....?

Clear Skies,

Dave

[Liquid360]

If you call OPT ask for sales manager Larry and tell him Nate from bama says hello.