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Just bought a Celestron Omni CG-4 mount!

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#1 joelimite


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Posted 29 April 2011 - 05:15 PM

Just picked up one of these from telescopes.com. $240 after a $15 discount, plus free shipping. Tried to order it from Astronomics, but they're out of stock and not getting any more in :(

Anyways, I'm excited to receive it. I'll be using it with my ED80 for visual and casual astrophotography. Anyone else using a CG-4 for these purposes with a similar size scope? I plan to pick up an ED100 scope in the future and hope this mount will be stable enough. From the maximum load specs, it looks like it shouldn't be a problem.

#2 Nippon


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Posted 29 April 2011 - 05:31 PM

I have a CG4 that I put a TV 85 on and I am pleased with it. Mine has a single axis drive that I bought from Orion. Orion's Astroview is the same basic mount so their single axis drive works perfectly on the CG4. I don't do astro photography with it and never will but not because of the mount. It's just that AP is too much like work for me, literally.

#3 Doug76


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Posted 29 April 2011 - 09:05 PM

Actually, the CG-4 is a much upgraded version of the Astroview/EQ3 mount. No comparison really.
Bearings on both axis', much better tripod, and it just plain looks better!
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#4 punk35


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Posted 30 April 2011 - 10:08 AM

yes the cg4 will be a nice match for your ed80 and should handle an ed100 fine for visual. i had the old style cg4 with the spindly legs and it did pretty good with the c4r it came with. the new style, as doug76 pointed out, has a much better tripod, so no problemo with the future ed 100. heck it might even do well with a st120 for visual, but that is speculation on my part as i havn`t tried it. enjoy your new mount

#5 rkayakr


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Posted 30 April 2011 - 01:48 PM

I just got a CG4 mount as part of the Celestron 102ED package that was on sale at Astronomics. The mount handles the 8 lb 102 OTA with ease and feels like it could handle a heavier scope. I do visual so I can't comment on the astrophotography.
I see that they also sell the CG4 mount with a 120 mm OTA.

#6 joelimite


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Posted 01 May 2011 - 12:29 PM

Thanks for the responses, everyone. As far as astrophotography goes, I don't plan on pursuing it seriously. Just want to take some 20- to 30-second exposures using my DSLR camera. Would I need the dual-axis drive for this, or would the single be enough? I'm mainly a visual observer, and I like the idea of being able to track planets as well.

#7 watcher



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Posted 01 May 2011 - 04:45 PM

Mine was great for visual even with the 120 F/8.3. I use the tripod now with my Vixen GP2, and put aluminum legs on the CG-4 to use as a grab&go for my AT 80ED.

I would think you could get by with the single axis drive for limited AP, just get an accurate drift alignment when you're setting up for AP.

There is lots of information on the net for tuning up CG-5 mounts that would be beneficial for the CG-4 as well. For AP you might look into tightening up the tolerances, and getting rid of any slop in either axis. This will imrove AP performance. CG-5 tuneup guide

#8 trist007


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Posted 12 January 2015 - 10:50 AM

Does the mount need power to use the optional polar scope?



Edited by trist007, 12 January 2015 - 11:17 AM.

#9 MikeMiller


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Posted 16 January 2015 - 09:43 PM

Tristan, the polar scope just has pictures of the constellations  near the pole (depending on which pole you are near), with it you use the alt-az bolts to line it up for polar. I don't use the polar scope on my cg4, as just lining up the finder with the scope in the home position is good enough for the decently wide field scopes I use on it. You could also sight through  the polar scope hole sans scope.


My only complaint about mount is the "slop" in the dec axis slow motion control. I couldn't find a way to tighten it. I guess the gears are too big. Would love to hear what other people do about that.

Edited by MikeMiller, 16 January 2015 - 09:54 PM.

#10 T1R2


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Posted 17 January 2015 - 03:47 AM



My only complaint about mount is the "slop" in the dec axis slow motion control. I couldn't find a way to tighten it. I guess the gears are too big. Would love to hear what other people do about that.

Mike, the slop can be removed by loosening/or tightening the grub screw, that is the black one in between the two chrome ones, down the little hole.

when you loosen it you will fell the tension get tighter, and when you tighten it you will feel the tension get lighter, try a little stiffer tension. you can also take the worm gear housing off completely and add washers to the bolts that attach it to the upper part of the saddle to help square it up. 


the CG4 is a great little eq mount, its rock solid even with my AR127, but there will be focusing wobbles at high power, low power, it will not shake at all.

#11 bobzeq25


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Posted 17 January 2015 - 12:21 PM

Doing DSO astrophotography with this mount will be...  challenging.  Let us know how it goes.


What's wrong with using the AVX in your sig?

Edited by bobzeq25, 17 January 2015 - 12:22 PM.

#12 T1R2


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Posted 17 January 2015 - 03:39 PM

I think the CG4 will be a little lacking for AP, could work great with the RA drive for mounting a stand-alone camera for wide field you will want the polar scope if not doing a drift alignment and would do well with short fl camera lenses, the ED80 you might could also get away with using, but the CG4 is more for visual use and the AVX is great for casual AP, or even really good longer fl AP. with guider

#13 AhBok


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Posted 20 January 2015 - 11:03 AM

I have the CG4 with my 150mm F5 reflector. I use the polar alignment scope in order to get excellent accuracy using the DEC circle. I am an old timer who enjoys finding objects many different ways from goto to starhopping and to alt/az and eq setting circles. With the CG4, I polar align with the polar scope (never takes more than 15-20 sec). Then I adjust Dec for the object I want to view. Then I move the RA to the general area of the sky and sweep in RA to find the object with a low power eyepiece. Works great. You don't need a polar scope for star hopping or tracking for visual, but it does help for finding objects using the sweeping method I outlined.

Neat little mount and such a bargain.

#14 buddyjesus



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Posted 25 January 2015 - 07:26 PM

I am very happy with how my scope performs on my nearly twenty year old CG4.  I think it could handle visual with an 80mm fine and be a great mount for piggyback imaging.

#15 beanerds



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Posted Yesterday, 05:42 AM

I had one under a 102mm Celestron f9.8 achromat and it carried this OTA with ease , very solid , I like many tried AP so sold the 102 and grabbed an Orion ED80 ( my first of MANY APO's ) and this set up with basic dual axis drives did very well , with good polar alignment I could get 3-5 miniutes without trailing .


But like many found AP , #1- to time consuming and #2- way to expensive for my lifestyle and gave it up .

I now use a Vixen GP ( the CG4 original )  and HEQ5 ( Sirius ) as purely visual only observing , but the Omni CG4 is a great mount in all ways  , as long as you don't over load it so an ED 80 is perfect for what you want , enjoy it .



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