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#1 PhilCo126

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Posted 08 March 2009 - 01:22 PM

As I'm hesitating of buying a Celestron CGEM mount, I would like to hear what are the pro's and contra's about this mount.
So far I know:

Pro CGEM:
40,000 elements in NexStar database against 13,400 in Synscan EQ-6
Easier setup for GoTo enabled observation (e.g. daylight solar system)
Better servo motors
Two years warranty


Contra CGEM
Overall plastic look & feel of outside?
Handset cord way too short?
Saddle knobs too smooth?


:confused:

#2 mclewis1

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Posted 08 March 2009 - 02:19 PM

Assuming you're comparing a CGEM to an EQ-6 and not an NEQ-6 add a Losmandy D type saddle to the CGEM pro column.

Other CGEM pros ... Larger Alt and Az ajustment knobs, more mature software.

Other cons ... hardware not as well proven.

#3 PhilCo126

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Posted 08 March 2009 - 02:33 PM

Don't know about the NEQ-6 but would a CGEM also require this overhaul/maintenance:
http://avex.org.free.../index-eng.html
:p

#4 divers

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Posted 08 March 2009 - 03:07 PM

Out of the box...mine has NO issue's at all with the exception of my pickyness over the saddle...not a con, just a note. I love the mount. Tracking is great, goto is great. Seems that someone made improvements to the Atlas and called it a CGEM.

#5 Lane

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Posted 08 March 2009 - 03:10 PM

I got a handset cord extender from Scopestuff and that eliminates the short hand controller cord issue. IMO that was the only real con for the CGEM and easily corrected. I don't know why you think it looks plastic because it is completely metal as far as I can tell. Only those big knobs are plastic and I also replaced them with star shaped knobs, but mainly so it would fit in my Hardigg storage case with the knobs still attached.

#6 Skylook123

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Posted 08 March 2009 - 05:32 PM

My Atlas is over three years old and has been bulletproof for about 50 or more nights a year of visual use. I did replace the HC to mount cable that shorted about a year and a half ago.

#7 AntarcticDave

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Posted 08 March 2009 - 05:39 PM

I'm very happy with mine so far. It handles my 6" achromat easily, and I really like the new polar alignment algorithm - no more bending down to peer through a polar alignment scope.

#8 Olivier Biot

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Posted 08 March 2009 - 07:01 PM

I have seen the CGEM for the very first time this weekend on an astronomy event in northern France. It has a nice design, feels quite solid without being overly heavy. It's definitely a step up with respect to the proven EQ6/Atlas. This mount features some nice enhancements like more ergonomic polar height adjustment.

The counterweight shaft must be unscrewed from the mount head, as it does not retract into the mount (as with the HEQ5/Sirius and EQ6/Atlas).

#9 PhilCo126

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Posted 09 March 2009 - 02:30 PM

Glad to see lots of great comments, ordered mine but there's a six weeks waiting period... :doah:
:imawake:

#10 Skylook123

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Posted 09 March 2009 - 03:46 PM

Let me add a topic from beyond the fringe of normal use. The EQ6/Atlas/HEQ5/Sirius, using EQMOD, will allow satellite tracking. Now THAT's a capability not many folks talk about!

Just trying to throw another consideration into the mix.

#11 rmollise

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Posted 09 March 2009 - 04:07 PM

Don't know about the NEQ-6 but would a CGEM also require this overhaul/maintenance:
http://avex.org.free.../index-eng.html
:p


No...and neither does the EQ6/Atlas. Most of the overhauls were done on the early (non-go-to) EQ6, and the mount has come a long, long way since then. Sure, some people take their mounts apart, but some people immediately take their Porches apart to "make them better" too. The Atlas almost always works just find right outa the box.

Frankly, the CGEM and Atlas are sisters and are more alike than different.

;)

#12 Victory5

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Posted 09 March 2009 - 06:25 PM

I just purchased one last week. It is a solid mount. It does look plastic like, but it's solid metal.

Still getting used to it 1st GEM I have owned so I haven't determined the positive/ negatives. Does seem a tad noisy when slewing. However, it holds my TMB 130, 2 inch star Diag. a 31mm Nagler, and a heavy Williams optics view finder with no problem

#13 Victory5

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Posted 09 March 2009 - 06:29 PM

Does your CGEM slew with minimal noise?

#14 R Nitzel

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Posted 09 March 2009 - 07:58 PM

My CGEM's a little noisy - more so when fully loaded. The other night, I had my C8 with a DSI III attached, a short-80 with a ssag attached, and a 40D with a 100-400L. It seems to move about fine with that load (plus 1-17# and 2-11# CW's), but it did seem a little louder - or maybe I was listening more closely.

#15 Lane

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Posted 10 March 2009 - 03:33 AM

The CGEM definitely makes more noise when slewing, but it also slews faster. When slewing at the same speed they are pretty close to same noise level. The problem is that when you do a goto it always slews at the maximum speed. You can only control slewing speed for manual slewing. This is one thing I wish they would add to a future hand controller update, I know my old Meade lx200 allowed the max goto speed to be selected.

#16 t.r.

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Posted 11 March 2009 - 10:24 AM

Would the CG-5 pier extension fit the CGEM to get some height? The tripods are the same...

#17 LLEEGE

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Posted 11 March 2009 - 11:12 AM

I don't think they are, Tim.

#18 PhilCo126

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Posted 11 March 2009 - 12:39 PM

Although tripods look the same, the bolts might be slightly bigger on the CGEM tripod...

#19 Lane

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Posted 11 March 2009 - 01:15 PM

CGEM tripod leg diameter is all that is the same (both are 2"). Everything else is different.

#20 t.r.

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Posted 11 March 2009 - 01:19 PM

Is there a pier extension available for the CGEM then(I should say half-pillar)?

#21 Lane

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Posted 11 March 2009 - 01:37 PM

Not yet - I would own it if there was.

Here is what the top of the tripod looks like:

Attached Files



#22 t.r.

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Posted 11 March 2009 - 02:11 PM

Lane, thanks for the pic...did you by chance also have a CG5 to compare with? I always felt the 2" tripod on the CG5 was the weak link for stability and if its the same as the CGEM with a heavier head????? Not sure how much better the CGEM would be for 40#'s ya know?

#23 Lane

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Posted 11 March 2009 - 02:54 PM

I dont' own one but I have seen the top of the cg-5 tripod and it has the wider hole like most of the other scopes do. The cgem is the first one I have seen with that small mounting hole. In terms of stability the cg-5 is about equal to the sirius (heq5). The older sirius has 1.75" legs and is a little less stable, but the new one comes with 2" legs and seems to be the equal of the cg-5. But neither of these mounts come close to the atlas or the cgem in terms of stability. I think it is simply a matter of the more massive size of the mount heads. The atlas at 36 lbs and the cgem at 40 lbs with counterweight bars. The difference is like night and day in my opinion. To me the sirius and cg-5 really match up well with an 8" sct, but the cgem is well matched with the 11" sct.

#24 jrbarnett

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Posted 11 March 2009 - 03:20 PM

Is the CGEM perhaps the same as an Atlas in this regard? It certainly looks the same. If so, wouldn't the Atlas pier extension work? Orion sells them. I use one on my Atlas and if I switch to a CGEM (once it gets a bit more mature) in order to move over to Nexstar from Synscan, I assume the CGEM will fit not only my pier extension but also my Atlas-adapted Antares 48" pier.

I sure hope so.

Regards,

Jim

#25 Lane

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Posted 11 March 2009 - 03:36 PM

I have never seen the top of the atlas tripod but I thought it was the same as the sirius. Look at the measurement of the CGEM center hole in that picture above it is a little less than 1 and 1/4" in diameter. I think the atlas mount has a hole that is at least 3/4" wider than that.






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