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Jeff55
professor emeritus

Reged: 04/14/05

Loc: Boston MA

OK Who's Happy With Their CGEM
#3079380 - 05/01/09 04:24 PM

Came back from NEAF very impressed with the Celestron CGEM mount. Fit and finish was first rate...the mount responded with smooth motions. I know some have had significant "teething problems" with the first group of mounts BUT I'd like to hear what more recent buyers have thought. Thanks (I'm about to put my money down and just need those last few comments to know if I should buy now or wait).

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Trebor777
Hazy

Reged: 01/04/08

Loc: Connecticut - U.S.

Re: OK Who's Happy With Their CGEM new

new

[Re: Jeff55]
#3079480 - 05/01/09 05:13 PM

Also think about the Atlas EQ-G, which is a proven performer AND comes with a polar alignment scope. It's $1500. While the CGEM is a bit cheaper it doesn't have a PA scope and if you buy one, then you're paying more then the cost of the Atlas.

Something to think about...

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mclewis1
Thread Killer

Reged: 02/25/06

Loc: New Brunswick, Canada

Re: OK Who's Happy With Their CGEM new

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[Re: Trebor777]
#3079499 - 05/01/09 05:23 PM

I agree that the Atlas/EQ-6 is also a good mount to look at, but IMHO like the CGE (if you are using the 4.15 firmware) you don't need the polar alignment scope on the CGEM.

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Lane
Post Laureate

Reged: 11/19/07

Loc: Frisco, Texas

Re: OK Who's Happy With Their CGEM new

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[Re: mclewis1]
#3079668 - 05/01/09 06:51 PM

Randy - Polar Alignment scope? That's horse and buggy thinking

I have had mine since January and so far no problems at all. The GOTO performance, vibration damping times, hand controller, and low noise level are absolutely incredible compared to my old LX200.

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cuzimthedad
Just Be Cuz

Reged: 04/09/06

Loc: Sonoma, Northern California

Re: OK Who's Happy With Their CGEM new

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[Re: Lane]
#3079840 - 05/01/09 08:33 PM

I don't think the op requested info on the CGE or the Atlas. I too am interested in hearing recent CGEM owners opinions if they are out there.

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Moggi1964
Vendor - Astro Laugh

Reged: 11/07/05

Loc: Madison. NJ. USA

Re: OK Who's Happy With Their CGEM new

new

[Re: cuzimthedad]
#3079998 - 05/01/09 10:16 PM

I'm in the queue for one

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waassaabee
Post Laureate

Reged: 11/26/07

Loc: Central California Coast

Re: OK Who's Happy With Their CGEM new

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[Re: cuzimthedad]
#3080117 - 05/01/09 11:34 PM

Solid, accurate, and reliable. And a good looking mount too!

I am very happy with my CGEM. I've only had it out four or five nights, but they all been very productive and pleasant.
GoTo accuracy and tracking is incredible, even well past the meridian. I've gone 20 degrees past meridian imaging with no problems.
And mine sounds nothing like my CG5...

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AntarcticDave
sage

Reged: 02/03/09

Loc: Denver, CO

Re: OK Who's Happy With Their CGEM new

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[Re: waassaabee]
#3080121 - 05/01/09 11:36 PM

I've had mine since early January and am very happy with it.

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coopfore1
super member

Reged: 11/23/05

Loc: il

Re: OK Who's Happy With Their CGEM new

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[Re: AntarcticDave]
#3080187 - 05/02/09 12:15 AM

I got mine 1 month ago. I am very happy with it so far.I love the rt clock. No more entering time loc etc every time. No need for polar scope. The all star gets me as close as any other scope i have used with a polar scope. The go-to is really close. Set up the nextremote software tonight. It was really easy and seems to work just fine. Well, I am sitting here thinking of a complaint. Still thinking????? Make sure you purchase tru astronomics and get your discount.

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Doug6952
Pooh-Bah

Reged: 07/24/08

Loc: West Milford, NJ

Re: OK Who's Happy With Their CGEM new

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[Re: coopfore1]
#3080581 - 05/02/09 08:41 AM

I bought mine at NEAF. Even though mine has a problem with the DEC axis (being sent to Celestron for repair) it works well. I've had it out 3-4 times since I got it. The last night that I used it I did the all star align followed by drift alignment to check it and I had no drift for at least 5 - 10 min.

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Greg K.

Reged: 12/11/03

Loc: Clifton Park, NY

Re: OK Who's Happy With Their CGEM new

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[Re: Doug6952]
#3081273 - 05/02/09 03:23 PM

I'm happy with my CGEM. With 2 star align and a single calibration star I've had very accurate gotos, even if I only do a rough eyeball polar alignment.

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Trever
Post Laureate

Reged: 08/18/03

Loc: North Alabama

Re: OK Who's Happy With Their CGEM new

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[Re: Greg K.]
#3081580 - 05/02/09 06:38 PM

So far, it has worked great for me. But, I have only used it a few times due to bad weather every day.

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J_D_Metzger
Carpal Tunnel

Reged: 05/13/04

Loc: Tucson, AZ

Re: OK Who's Happy With Their CGEM new

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[Re: Trever]
#3081810 - 05/02/09 09:14 PM

I got mine about 3 months ago, I think. I use it with a C11, and I've been very happy with it. I've replaced the stock knobs with ADM versions, and replaced the stock counterweight bar with one from an SN-10 LXD75, which is a couple inches longer, so I could balance the C11 a little better...

I am a visual observer, and for my use, the GOTOs and tracking are excellent. I'll let others comment on using the mount for imaging...

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Lord Beowulf
Pooh-Bah

Reged: 10/13/08

Loc: Cedar Park, TX

Re: OK Who's Happy With Their CGEM new

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[Re: J_D_Metzger]
#3081850 - 05/02/09 09:34 PM

I've been happy with mine so far, now that I have it! I've only had a few nights of astrophotography so far, but it's done pretty well. I did have one night where I had problems with my plug-in power supply losing contact (not actually coming out, but just bad contact). I'll be switching to a screw-on connector as soon as I get around to ordering one. I'll post the part number when I have a chance.

Beo

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PhilCo126
Carpal Tunnel

Reged: 01/14/05

Loc: coastline of Belgium

Re: OK Who's Happy With Their CGEM new

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[Re: Lord Beowulf]
#3146778 - 06/05/09 04:49 AM

Another happy CGEM owner here... Solid, very accurate using tri-star align and reliable. And indeed the mount looks great in its 2 color black/orange scheme

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Jeff55
professor emeritus

Reged: 04/14/05

Loc: Boston MA

Re: OK Who's Happy With Their CGEM new

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[Re: PhilCo126]
#3146892 - 06/05/09 08:19 AM

Well I finally purchased one and I have to say I'm very impressed with fit. finish and performance. This mount has exceeded all my expectations so thanks to everyone for giving me the confidence to buy one. Also Telescopes.com appears to have the best offers on this mount and I've found them to be an excellent (after a false start) dealer.

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Moggi1964
Vendor - Astro Laugh

Reged: 11/07/05

Loc: Madison. NJ. USA

Re: OK Who's Happy With Their CGEM new

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[Re: Jeff55]
#3149270 - 06/06/09 05:15 PM

I'm happy with mine too.

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aljo
member

Reged: 06/19/08

Loc: Slovenia, Europe

Re: OK Who's Happy With Their CGEM new

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[Re: Moggi1964]
#3149289 - 06/06/09 05:22 PM

Could someone post "a lot" of pictures of CGEM

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mich_al
Pooh-Bah

Reged: 05/10/09

Loc: Rural central lower Michigan ...

Re: OK Who's Happy With Their CGEM new

new

[Re: aljo]
#3149495 - 06/06/09 08:17 PM

I've had mine a week plus one day and I'm happy with it. I've got to agree with the previous poster about the power connector. Absolute POS, comes loose all the time, ridiculous design for a cable that WILL be moving around alot. I stabilized the cable about 6" upstream from the connector on about day 3 and have not had a problem since. I'll keep watching here for the part numbers on those screw on connectors. I've also added an extention cable to the hand control and stabilized its cable on both ends. It REALLY should have a connector and not be hardwired on the controller side.
Fit and finish are mostly excellent (see focuser remarks below). The Goto function is amazing. I do a 2 star align with maybe another calibration star or two and sync to every every item I view through the night. New items often show up in the eye piece, almost always within the finder scope and have rarely been outside the finder. My focuser has a 'tight' spot in it. It doesn't affect performance but it ought to be smooth all around every rev. The tripod is beefy and needs to be, this thing is heavy. Make sure you lock down the extender legs tight. I almost lost it all to a leg slipping the first night. A complaint I do have is with the hand controller. The display intensity controls don't seem to do anything. There are two variable each 0-8, all settings seem the same to me, and all are too dim. With the current bright moon I can see most of what's shown but when the moon goes I'm gonna need a flashlight.

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Blixx
professor emeritus

Reged: 12/02/07

Loc: CO. Aurora, USA

Re: OK Who's Happy With Their CGEM new

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[Re: mich_al]
#3149509 - 06/06/09 08:29 PM

I haven't had a chance to get mine out but I did a test in my house. It seems pretty solid, my mount came with the screw in type power connector, which I think is a good thing.
Dan

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jbury
Vendor - ObserverPro

Reged: 02/02/09

Loc: Oregon, USA

Re: OK Who's Happy With Their CGEM new

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[Re: aljo]
#3149821 - 06/07/09 01:29 AM

I'm really happy with mine. This is the first mount that I've owned that's really capable of long-exposure prime-focus astrophotography. Here's a picture of my setup. My first photos taken with the mount can be found here, here, and here. The azimuth and altitude adjustments on the mount make it much easier to dial in on good polar alignment (especially when used with the 'All Star' polar alignment routine).

Josh

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aljo
member

Reged: 06/19/08

Loc: Slovenia, Europe

Re: OK Who's Happy With Their CGEM new

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[Re: jbury]
#3150411 - 06/07/09 12:38 PM

How much does the GPS module cost?

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Lord Beowulf
Pooh-Bah

Reged: 10/13/08

Loc: Cedar Park, TX

Re: OK Who's Happy With Their CGEM new

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[Re: mich_al]
#3150604 - 06/07/09 02:28 PM

Quote:

I'll keep watching here for the part numbers on those screw on connectors.

Sorry, I ended up rigging myself a 12V power supply to run dew heaters, etc. and thus switched to the 12V cord from Celestron. Never got around to ordering the connector from Mouser Electronics, but I believe it's this 5.5 OD/2.0 ID part. However, I never got a chance to go to Radio Shack and double-check the ID (they also have a 2.1 mm ID), so I'd recommend that before ordering one.

Quote:

My focuser has a 'tight' spot in it. It doesn't affect performance but it ought to be smooth all around every rev.

Of course a focuser isn't part of the mount... I'm assuming you bought a CGEM system. Which OTA?

Quote:

A complaint I do have is with the hand controller. The display intensity controls don't seem to do anything. There are two variable each 0-8, all settings seem the same to me, and all are too dim. With the current bright moon I can see most of what's shown but when the moon goes I'm gonna need a flashlight.

This doesn't sound right at all. Granted I haven't adjusted my CGEM HC brightness, but I have on my 8SE, and the CGEM HC is at default full brightness. It sounds like the backlight on your HC isn't working correctly.

Beo

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mich_al
Pooh-Bah

Reged: 05/10/09

Loc: Rural central lower Michigan ...

Re: OK Who's Happy With Their CGEM new

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[Re: Lord Beowulf]
#3152042 - 06/08/09 10:29 AM

Quote:

Quote:

I'll keep watching here for the part numbers on those screw on connectors.

Sorry, I ended up rigging myself a 12V power supply to run dew heaters, etc. and thus switched to the 12V cord from Celestron. Never got around to ordering the connector from Mouser Electronics, but I believe it's this 5.5 OD/2.0 ID part. However, I never got a chance to go to Radio Shack and double-check the ID (they also have a 2.1 mm ID), so I'd recommend that before ordering one.

After securing the flopping cable I don't think I'd bother to open the connection plate. If I get inside there for any other reason I'll probably replace the poewr connector.

Quote:

My focuser has a 'tight' spot in it. It doesn't affect performance but it ought to be smooth all around every rev.

Of course a focuser isn't part of the mount... I'm assuming you bought a CGEM system. Which OTA?

9.25 OTA. Turns out the tight spot was fixed by either adjusting the 3 screws or moving back the rubber handle/adjuster. Probably adjusting the 3 screws. It's now smooth.

Quote:

A complaint I do have is with the hand controller. The display intensity controls don't seem to do anything. There are two variable each 0-8, all settings seem the same to me, and all are too dim. With the current bright moon I can see most of what's shown but when the moon goes I'm gonna need a flashlight.

This doesn't sound right at all. Granted I haven't adjusted my CGEM HC brightness, but I have on my 8SE, and the CGEM HC is at default full brightness. It sounds like the backlight on your HC isn't working correctly.

Hmmm, that I'll have to look into, thanks for your input,

Al

Beo

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Lord Beowulf
Pooh-Bah

Reged: 10/13/08

Loc: Cedar Park, TX

Re: OK Who's Happy With Their CGEM new

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[Re: mich_al]
#3152105 - 06/08/09 11:06 AM

Al:

The connector would be a replacement for the end of your power supply cable, not one that would go in/on your mount. It provides the same retention collar that the 12V lighter adapter that came with the CGEM has. You'd have to chop off the connector on the end of your power supply and solder this one on. The only thing I was recommending there was to take your current adapter to RadioShack and double check which size the center pin is by plugging it into the various sockets they sell. I did that back when I had to replace the damaged connector on my power supply after having a cord wrap problem on my 8SE, but I don't remember what it ended up being.

Glad to hear you resolved your focuser issue. Good luck with the HC!

Beo

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donsinger1
sage

Reged: 10/28/07

Re: OK Who's Happy With Their CGEM new

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[Re: Blixx]
#3152116 - 06/08/09 11:15 AM

Love mine too...same complaint about the DC connector, but that is relatively minor. Gotos and tracking are great, and I have done 5 minute guided images at 630mm FL with nice round stars. So, for the price, it cannot be beat.

Don

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mich_al
Pooh-Bah

Reged: 05/10/09

Loc: Rural central lower Michigan ...

Re: OK Who's Happy With Their CGEM new

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[Re: Lord Beowulf]
#3152562 - 06/08/09 03:58 PM

Beo

For the first time I just looked at the telecope end connector on the cigarette lighter cable. Wow, that's nice. That's just what the cable I'm using needs ! I'll look around for one, Thanks. As for the HC, well it does have different intensities, can't explain why I thought it wasn't doing anything. The bottom line though is it's still too dim for my old eyes in the dark.

Al

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dvb
different Syndrome.

Reged: 06/18/05

Loc: Vancouver, Canada

Re: OK Who's Happy With Their CGEM new

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[Re: mich_al]
#3153398 - 06/09/09 01:36 AM

I can see that a precise polar alignment with a scope may not be needed for GoTos, but surely the RA axis has to be carefully polar aligned to permit accurate tracking?

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jrcrilly
Refractor wienie no more

Reged: 04/30/03

Loc: NE Ohio

Re: OK Who's Happy With Their CGEM new

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[Re: dvb]
#3153422 - 06/09/09 02:16 AM

Quote:

I can see that a precise polar alignment with a scope may not be needed for GoTos, but surely the RA axis has to be carefully polar aligned to permit accurate tracking?

Yes. Nearly all EQ mounts track only in RA are thus dependent on polar alignment for tracking. A few exceptions exist, but the CGEM isn't one of them.

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FlyingAstronomer
member

Reged: 12/31/08

Loc: Lawrenceville GA

Re: OK Who's Happy With Their CGEM new

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[Re: jrcrilly]
#3153425 - 06/09/09 02:27 AM

But the CGEM has an alignment routine to help, no? It's not supposed to need a polar scope, though it does need polar alignment.

Even if the mount did track in declination this would not obviate the need for polar alignment for imaging, because the field would rotate.

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Lord Beowulf
Pooh-Bah

Reged: 10/13/08

Loc: Cedar Park, TX

Re: OK Who's Happy With Their CGEM new

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[Re: FlyingAstronomer]
#3154132 - 06/09/09 02:17 PM

Roger,

The new Celestron GEM firmware introduced with the CGEM does two things. First, it allows you to add up to three additional "calibration stars" to the two-star alignment. Normally the alignment is done in the West, and then the calibration stars are in the East. If all goes well, after the first calibration star is added, the second calibration star selected will be darn near the center of the field when the mount slews to it. My experience is that if it's not, you probably are either so far off your polar alignment, or just really messed up the initial alignment, to the point that you're not going to get a good alignment with more calibration stars anyway. However, if you've done everything right, once you've added a fourth star, your goto accuracy is typically excellent. The fifth star might be useful if you're not 100% happy with the goto on the fourth, but otherwise I think most people stop at four.

Once you have the mount well aligned and calibrated, you then use the new All-Star polar alignment to adjust the polar alignment of the mount. It's similar to the wedge align supported by previous alt-az models, but instead of using Polaris, you select a star away from the horizon or meridian (one that gives good declination information as well as RA) and it will automatically slew to the star and start a synch operation. Once you align the star to synch to it, it will then slew to where the star SHOULD be if the mount was properly polar aligned. At that point, you adjust the alignment knobs to re-center the star and you're pretty well polar aligned. The residual error in your alignment will be a function of how well aligned/calibrated the mount was to begin with, and the play in the knobs and gearing as you synched and then manually aligned the star. My experience has been that the remaining error appears to be within the resolution of the adjustment screws (i.e. no more than a small fraction of a turn off from the desired location).

The one time I spent any time considering a drift alignment after the All-Star polar alignment appeared to show that the only drift I had was in RA, most likely due to the PE in the worm gear.

Beo

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donsinger1
sage

Reged: 10/28/07

Re: OK Who's Happy With Their CGEM new

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[Re: Lord Beowulf]
#3154674 - 06/09/09 07:52 PM

Beo:

Great explanation....I have marks on my porch where the three feet of the tripod are to go, and marks on my mount to approximate where polar alignment is. I then align as per Beo's description, then use the Polar Align routine, followed by another two star plus calib alignment, and I am off to the races imaging. So far, I have done 5 minute subs using a C6 at F6.3 (945mm FL) and stars were round and just fine...in fact, 5 minutes in my light polluted location is too much and produces sky fog, so that was overkill.

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ZRX-Steve
sage

Reged: 03/31/08

Loc: Phoenix, Arizona

Re: OK Who's Happy With Their CGEM new

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[Re: donsinger1]
#3155037 - 06/09/09 11:18 PM

I had an early CGEM. It was a good mount and I loved the all star polar alignment. No polar scope needed or wanted. But the PEC was high at 30 seconds peak to peak. I use Mallincam and want to do unguided 56 second integrations and so I returned it. If you are guiding, the PEC doesn't matter so much.

I replaced it with a used G11 and I'm still getting used to it. I really do miss the All Star alignment though. It spoiled me forever.

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yg1968
Carpal Tunnel

Reged: 01/26/04

Re: OK Who's Happy With Their CGEM new

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[Re: ZRX-Steve]
#3155801 - 06/10/09 01:26 PM

Jbury,

Very nice images.

I wish Synta would also upgrade the firmware on the Atlas for the meridian options that are available on the CGEM. The meridian crossing options exist if you are using EQmod but I am used to the hand controller.

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Mike Harvey
scholastic sledgehammer

Reged: 03/01/04

Loc: Orlando, FL.

Re: OK Who's Happy With Their CGEM new

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[Re: yg1968]
#3156928 - 06/11/09 03:05 AM

I've had mine for 6 months and have had zero problems and only one real complaint - when I use a Schmidt-Newt or Newt, the mounting rings extend the balance point beyond what the polar shaft can handle with approximately equal counterweights. It takes about 35lb. to balance a 20lb. OTA!
I've ordered a longer shaft.
As pointed out by others...there is absolutely no need for a polar scope. The Polar Align function in the mount's software does a great job.

Mike

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chicot
sage

Reged: 09/30/08

Loc: Liverpool, UK

Re: OK Who's Happy With Their CGEM new

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[Re: ZRX-Steve]
#3157256 - 06/11/09 11:01 AM

30 seconds peak-to-peak?! Surely that PE is untrained? If so, why didn't you just train the PEC? I have a 10-yr old LX200 and I have trained the PEC so that the PE is 5 arcseconds peak-to-peak. I can do 2 minute unguided exposures with no trouble. I would be very suprised if a modern GEM couldn't manage at least that.

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jacktechie
super member

Reged: 03/20/08

Loc: SF Bay Area

Re: OK Who's Happy With Their CGEM new

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[Re: chicot]
#3157287 - 06/11/09 11:27 AM

Be surprised then. I have a CGE mount (mid April 2009) out of the box with +50 / -20 arcsec PE. It's back at the factory to be fixed. Full dissertation on Yahoo Groups.
Jack

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chicot
sage

Reged: 09/30/08

Loc: Liverpool, UK

Re: OK Who's Happy With Their CGEM new

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[Re: jacktechie]
#3157338 - 06/11/09 12:01 PM

But is that before or after PEC training or does the CGEM not have PEC? If it's going back to be fixed, presumably that's not a typical performance?

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Tim C
scholastic sledgehammer

Reged: 11/11/07

Loc: Marietta, GA

Re: OK Who's Happy With Their CGEM new

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[Re: chicot]
#3157446 - 06/11/09 01:14 PM

PEC made very little difference on mine. Pempro took it from 30 to 26. About the same result using the celestron tool.

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ZRX-Steve
sage

Reged: 03/31/08

Loc: Phoenix, Arizona

Re: OK Who's Happy With Their CGEM new

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[Re: Tim C]
#3157539 - 06/11/09 02:10 PM

PEC training didn't help that much. My results were similar to Tim's. Tim had one of the early CGEMs and was the first to document PEC results. Here's a link to Tim's thread showing his PEC results.

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chicot
sage

Reged: 09/30/08

Loc: Liverpool, UK

Re: OK Who's Happy With Their CGEM new

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[Re: Tim C]
#3157541 - 06/11/09 02:11 PM

That's pretty awful. Not the mount for AP then.

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ZRX-Steve
sage

Reged: 03/31/08

Loc: Phoenix, Arizona

Re: OK Who's Happy With Their CGEM new

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[Re: chicot]
#3157547 - 06/11/09 02:15 PM

I don't know about that. If you're guiding, it probably doesn't make that much difference. Certainly folks are getting great results from them.

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Tim C
scholastic sledgehammer

Reged: 11/11/07

Loc: Marietta, GA

Re: OK Who's Happy With Their CGEM new

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[Re: ZRX-Steve]
#3157590 - 06/11/09 02:41 PM

Yeah, I got pretty decent results guiding after i learned to keep the guide exposures short. Many of the shots in my gallery were with the cgem. I got tired of fooling with the PEC though. Overall there were a lot of things to like about this mount.

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chicot
sage

Reged: 09/30/08

Loc: Liverpool, UK

Re: OK Who's Happy With Their CGEM new

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[Re: ZRX-Steve]
#3157750 - 06/11/09 04:22 PM

I'm something of a newbie when it comes to guiding so maybe it is possible to guide out such a large error, especially if it's smooth. Just a bit of a eyeopener to me that it's unguided performance should be so inferior to that of a mass-market fork mount.

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jrcrilly
Refractor wienie no more

Reged: 04/30/03

Loc: NE Ohio

Re: OK Who's Happy With Their CGEM new

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[Re: chicot]
#3157769 - 06/11/09 04:34 PM

Quote:

I'm something of a newbie when it comes to guiding so maybe it is possible to guide out such a large error, especially if it's smooth. Just a bit of a eyeopener to me that it's unguided performance should be so inferior to that of a mass-market fork mount.

The mass market forkmounts tended to be about that bad out of the box, also. PPEC corrects it - but for that to happen one must have guiding set up perfectly, to make the training valid. If PEC fails to improve PE then either the error is NOT PE or PEC training wasn't effective.

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ZRX-Steve
sage

Reged: 03/31/08

Loc: Phoenix, Arizona

Re: OK Who's Happy With Their CGEM new

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[Re: jrcrilly]
#3157931 - 06/11/09 06:29 PM

Quote:

The mass market forkmounts tended to be about that bad out of the box, also. PPEC corrects it - but for that to happen one must have guiding set up perfectly, to make the training valid. If PEC fails to improve PE then either the error is NOT PE or PEC training wasn't effective.

I won't disagree. My first experience with PEMpro was with the CGEM and some of it may have been inexperience.

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jacktechie
super member

Reged: 03/20/08

Loc: SF Bay Area

Re: OK Who's Happy With Their CGEM new

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[Re: chicot]
#3158547 - 06/12/09 03:25 AM

Quote:

30 seconds peak-to-peak?! Surely that PE is untrained? ... I would be very suprised if a modern GEM couldn't manage at least that.

I have the $3000 CGE mount that is twice the price of the CGEM. The PE may be smooth but I'm not going to settle for something that is not within normal. Most people get 30-40 arcsec P-P for older CGEs and current ones about 20-30 P-P. So if Celestron Tech Support and Customer Relations were surprised at my +50/-20 numbers and urged me to send it in, they will get a chance to fix it to spec. But then, they do not publish PE specs for the CG5, CGEM or CGE, but only for the CGE Pro at +/-9 arcsec. My mileage varied.
Jack

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chicot
sage

Reged: 09/30/08

Loc: Liverpool, UK

Re: OK Who's Happy With Their CGEM new

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[Re: jrcrilly]
#3158565 - 06/12/09 04:20 AM

Yes, my PE was about 36 arcseconds peak-to-peak. Pempro performed miracles to get it down to just under 5 arcseconds. I'm not sure I really understand your point about the guiding needing to be perfect?

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jacktechie
super member

Reged: 03/20/08

Loc: SF Bay Area

Re: OK Who's Happy With Their CGEM new

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[Re: chicot]
#3158974 - 06/12/09 12:19 PM

I just want a "normal" mount like most people. I have been using an Orion Starshooter autoguider, PHD Guiding and/or Pempro through a 80mm f6.25 refractor. Most of the time I can't get through enough worm cycles to train PEC - the star will just leave for whatever reason. Every now and then, I see a 2+ arcsec ramp. I would have kept it if it had a 40 P-P meaning ramps would probably not be as steep. Whether it's the mount, atmosphere, guiding settings (changed often) or anything else, having spent many nights trying to adjust worm block, binding, etc. I just sent it back. Seems reasonable enough.
Jack

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chicot
sage

Reged: 09/30/08

Loc: Liverpool, UK

Re: OK Who's Happy With Their CGEM new

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[Re: jacktechie]
#3158999 - 06/12/09 12:34 PM

I agree. If it is an atypically bad example then sending it back is the right thing to do.

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airydisc
member

Reged: 01/23/07

Re: OK Who's Happy With Their CGEM new

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[Re: Blixx]
#3160904 - 06/13/09 03:23 PM

Just got it last night. I have to admit that it looks very impressive, but I was immediately troubled by the amount of slop (or play) in both RA and DEC axes. I haven't measured it (clouded over last night) but I'm guessing it's at least an arcminute. Is this normal? How do you adjust the worm gear mesh? I don't see anything about it in the manual.

Greg

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waassaabee
Post Laureate

Reged: 11/26/07

Loc: Central California Coast

Re: OK Who's Happy With Their CGEM new

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[Re: airydisc]
#3162110 - 06/14/09 09:51 AM

Greg, That doesn't sound right... My CGEM has no slop at all, but I believe there are backlash settings you can adjust in the hand controller. But if it bothers you (and it would me), I'd be on the horn to Celestron.

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Doug6952
Pooh-Bah

Reged: 07/24/08

Loc: West Milford, NJ

Re: OK Who's Happy With Their CGEM new

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[Re: waassaabee]
#3162202 - 06/14/09 10:58 AM

To adjust the worm mesh:

Loosen the 4 bolts that hold that axis down.
there are 2 set screws that need to be adjusted on each axis. The one closest to the motors/worm (there are round black covers on the outside) if you turn this in it loosens the gear mesh and turning it out will tighten. The other set screw (180° from the first) has the reverse effect (DO NOT over tighten this set screw)

After adjustment is done. tighten the 4 bolts.

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airydisc
member

Reged: 01/23/07

Re: OK Who's Happy With Their CGEM new

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[Re: Doug6952]
#3162242 - 06/14/09 11:26 AM

Thanks, guys. I've e-mailed Celestron and will try to contact them Monday. I'm comfortable with making the adjustment, but want to make sure it doesn't void the warranty, since the manual doesn't say anything about it. My Losmandy mount describes the procedure in detail, understanding that it is essential to proper operation of the mount.

Greg

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chollman
sage

Reged: 04/24/08

Re: OK Who's Happy With Their CGEM new

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[Re: airydisc]
#3162645 - 06/14/09 03:48 PM

I love the CGEM. Have had it for a few weeks now. It takes a few times out to learn but I am happy to say it gets better every time out. The polar alignment is excellent. This mount tracks perfectly. Also "trained" the mount for the tube to not hit the legs, as I use an 8" f/8 newt. This also works perfectly. I also switched out the tubing legs for shorter, heavier ones from the local hardware store. Celestron has made this easy to do with 4 set screws. Kudos to Celestron for making such a good mount affordable...Charlie

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PhilCo126
Carpal Tunnel

Reged: 01/14/05

Loc: coastline of Belgium

Re: OK Who's Happy With Their CGEM new

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[Re: chollman]
#3175793 - 06/22/09 05:46 AM

Looks like most of us are happy with the CGEM, but who replaced some "plastic" parts with ADMaccessoires and are these worth the "little" investment?
http://www.admaccessories.com/Miscellaneous_CGEM.htm

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