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New VX or good used CGEM

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#26 Raginar

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Posted 17 April 2013 - 08:12 AM

Martin,

I used a C5 on my CGEM. Wonderful little telescopes with a great FOV.

#27 orlyandico

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Posted 17 April 2013 - 09:37 AM

The 8/3 is a non-integer gearbox harmonic in the CGEM that is impossible to remove with periodic error correction.

On my CGEM the magnitude of the 8/3 is about 22 arc-seconds (even more than the worm fundamental of 16 arc-seconds). But on most CGEM's the 8/3 is only about 6 arc-seconds. So PEC on these mounts can reduce total PE from around 30" to 7" or 8".

#28 Mike X.

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Posted 17 April 2013 - 06:24 PM

The azeq6 is a little lighter than the Cgem but it's still more than twice the weight of a cg5. It weights like an atlas more or less. Less than a kg lighter.
Personally I noticed great difference in stability in confront with my cg5 while it maintains portability.

#29 oo_void

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Posted 17 April 2013 - 06:25 PM

If you're guiding, you don't really need to use PEC (I've seen arguments ranging from it get in the way to it couldn't hurt, but not a must have). PEC is useful for unguided imaging, but expectation should be set appropriately, we're talking a $1.5k mount, not a $10k direct drive.

Bottom line is that the CGEM is a fine and robust mount for the money. Someone posted a few messages back about at AT6RC with an ST80 piggy-backed on a VX. That was the config that drove me to upgrade from a CG-5 to a CGEM. I found the highly centralized load to be just a bit too much for the CG-5 DEC access. In fact, I always had trouble with DEC corrections until I upgraded. That said, I have yet to use, or know anybody else directly who owns a VX.

#30 MartinTreadgold

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Posted 18 April 2013 - 04:38 AM

Martin,

I used a C5 on my CGEM. Wonderful little telescopes with a great FOV.


I've ran out of money now.. but I plan to upgrade the OTA to an 8 inch SCT, or Edge HD... :)

#31 MartinTreadgold

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Posted 18 April 2013 - 04:52 AM

I just bought the new Celestron Advanced VX mount, and i took it on a weekend trip to Germany, and it was brilliant. The price is very reasonable, 750 Euros here. It's really easy to set up without any fuss. Its a big improvement on the CG-5 mount, and works equally as well as the CGEM mount. As the CGEM mount is bigger, it can handle more weight. The CGEM mount handles upto 40lbs whereas the AVX mount is 30lbs, so weight is the only thing you have to consider here. If you don't plan to use more than 30lbs, go for the VX mount, its newer with more up to date hardware.

See the photo attached of it nicely set up with a 5" Nexstar SCT

Martin, I have an LXD75 which I think is substandard for my NP127is (about 7.5 kg, or 16 lb or so). Do you think the AVX would be good with the NP127is? Does it really feel that much more substantial and stiffer than the CG-5?

The CGEM and Skywatcher AZ-EQ6 have caught my eye, but both these mounts are a lot heavier than the CG-5/AVX class mounts, and portability is an issue for me. Thanks, Fox


I'd say the AVX mount is still just about portable, not too heavy. The Tripod legs are really heavy duty, infact they are the same tripod legs as the NEQ6 :) :) just a different colour, NEQ6 is white, AVX black :p :p

The AVX holds upto 30lbs, whereas the CGEM mount is 40lbs according to the specs on celestrons website. (thats probably including the counterweight also)

If you have heavier than 30lbs optics in total, go for something more substantial such as the NEQ 6, but then you lose portability etc

If weight isn't an issue, sure, go for the VX mount. Celestron have made a great product. It feels really robust.

I've been reading a few review sites and a lot of people say this a great improvement on the CG-5 mount.

All my Astro buddies on last weekend's trip were pretty impressed with it, and they all have NEQ6 mounts.

So overall, when buying, you need to consider, the weight of your OTA, +weight of a DSLR camera, additional finder scopes, and other accessories... PLUS.. the weight of the counterweight = overall load on the mount.. and if all that exceeds 30lbs, you need a more heavy duty telescope than the AVX

#32 FoxTrot

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Posted 18 April 2013 - 07:09 AM

Thanks Martin, Fox!

#33 starbob1

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Posted 18 April 2013 - 07:18 AM

I think the 30lb linmit is for payload the buisness end' Not counterweight also.

#34 MartinTreadgold

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Posted 18 April 2013 - 01:22 PM

here's some close ups of the mount

Attached Files



#35 MartinTreadgold

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Posted 18 April 2013 - 01:26 PM

and base plate of the tripod

Attached Files








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