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Equipment Discussions >> Mounts

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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
CGEM vs CGEM DX
      #6135945 - 10/13/13 10:12 PM

I have seen where some post or say they have cogging and trackibng issues?? I have also heard that the issues have been addressed in the new mounts being made now? Then have heard that the difference in the motors/gears between the two has the DX with a slight advantage? Any input from users, and regrets over purchase, or thrilled at purchase?? Thank you, Kasey

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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6135985 - 10/13/13 10:30 PM

No difference in motors or gears. They both are subject to the cogging effect and 8\3 error equally as these are problems with the servos. Celestron has some beta software working on a fix for the cogging. Not all mounts suffer to a significant degree with either problem.

I have a CGEM. Mine exhits no cogging problem but significant 8\3 error. This error makes PEC useless and guiding at long FL problematic. The software is fantastic. Great pointing accuracy and an easy and accurate ASPA bonus. The price is good also. That said I wish I had spent more on the mount and got something better. I have my hopes on a EQ8 if\when they are released, provided I can get my finances back in shape.


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johnd39818
member


Reged: 12/31/12

Re: CGEM vs CGEM DX new [Re: Stew57]
      #6138240 - 10/15/13 01:43 AM

Ive owned my DX for 3 months now with no issues at all. Able to run 10 min subs flawlessly and GOTO's are dead on.

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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: johnd39818]
      #6138739 - 10/15/13 10:30 AM

Thank you Mark and John,
Thats what am looking to do right now for a while, is run unguided with video cam for about 2 minutes, from things have read and your 10 min (guided subs) sounds pretty good. Am using a 9.25 (deforked) right now on a CG-5. Mark, I checked on that EQ-5, pre-order is about 5K I think. Thats a big step up from 2K for CGEM-DX .. I found something on a sale sight that compared the CGEM vs DX and it said there was an upgrade in the motors or something, I will try to find it. Dis you ever consider the Losmandy G-11? Thank you both for your time input and hepl, Kasey


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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6139033 - 10/15/13 01:10 PM

I can't see doing 2 min unguided even with a videocam at all. Even with shorter focal lengths the PE is going to be too great. Less than 20 arcseconds is good for a CGEM. PEC won't takeout the 8\3 error, and will in fact make it worse in some areas . A small guider (I use a 50mm finder as guidescope) will sufice for video.

I would be hesitant to buy from someone that advertises different motors or gears in the DX. There was a different MC board for awhile though. It allowed more current flow to the servos. Join teamcelestron and inquire there, or email celestron directly. You may get to discuss with an engineer.


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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: Stew57]
      #6139332 - 10/15/13 03:45 PM

Thank you again Mark,
I had seen somewhere that the DX drives the motors a little smoother and better than the CGEM, but that may have been before motor board upgrade. How long have you gone unguided with yours? I have a SSAG set-up from when I had it mounted on the CPC., is all mounted ready to go for over a week now on my CG-5 but as normal the weather has been the pits,,,. I just didn't think most video guys were guiding, I'm VSS+ so am 2 minute max exposures. I have been signed up on Team Celestron for a little while now and have researched the cogging. From all I can get they speak of an upgrade (31.15/31.33) that resolved it?? I cannot find anything about 8/3 error tho.

I did find something interesting tho, the ability to do a tandem mount (like the EQ-45?)? You ever tried tt? ""Tandem support (the ability to turn the Dec axis 90 degrees and mount multiple optical tubes side-by-side) is now available for firmware versions GEM 4.15 and higher for Celestron’s German equatorial mounts."" Thank you again,
Kasey


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dmdouglass
professor emeritus


Reged: 12/23/07

Loc: Tempe, AZ
Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6139654 - 10/15/13 07:15 PM

Tandem mount...
Yup !! And it works too.

See images at: http://www.az-dahut.net/

[ Or, just look to the left at my avatar... ]

That is my backyard observatory.

Edit (Add): Of course, you do need an accessory from ADM for the "side-by-side" mounting...
http://admaccessories.com/D_Series_SBS.htm

Edited by dmdouglass (10/15/13 10:12 PM)


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A. Viegas
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6139965 - 10/15/13 10:45 PM

CGEM vs. CGEM DX is really a matter of cost and basically $500 when all is said and one, whether you buy new or used... What do you get for the extra $. Basically a better tripod, beefier counterweight bar and i suppose it's debatable if the motor control,board is better in th CGEM DX or not...

For a 9.25" the difference between CGEM or DX is probabl not worth $500... A 11" probably give the edge to the DX, I think 70% I would go with DX with 11"... A 8" is probably 70% better value on the plain CGEM and your 9.25" is more like 50/50 in terms of value proposition to the DX...

If you are planning to really upgrade in 3-5 yrs to an AP or Paramount, then I would say just get the CGEM and with resale value you probably do on... If on the other hand this next mount is close to your final mount purchase, then I would get the DX.

If you plan to guide, then the CGEM + DX are mostly comparable up to 2 mins... Given the savings I would say go for he CGEM ... I chose the CGEM because I bot it at NEAF, got a great deal and best of all saved enough,to buy more gear... I use it with my 8" and C80ED piggybacked...

Al


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Stargazer78
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Reged: 03/05/13

Loc: Susanville California
Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6140178 - 10/16/13 01:25 AM

You will not be disappointed if you go with the DX. That being said it is a heavy mount but I purchased mine as a final mount. I plan on getting a 10 inch R/C and call it done for my asyrophotography hobby. I have not experienced any issues at all with mine. For the extra payload capacity it a great deal.

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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: Stargazer78]
      #6140585 - 10/16/13 10:19 AM

Thank you all, and yes Al this should be the final mount for me; if I ever upgrade to C11 or the R/C Chris is using, I just want something that can handle it and not worry about weight issues. So would probably be the DX.. I don't figure on any pictures I take gracing the walls at NASA, but would like fairly good quality,,, would be nice to be able to unguided fro a couple minutes...
The Atlas gets good reviews but is only rated to 44 lbs,,, and new handset has ASPA.
I did copy and post a coment on Team Celestron site referencing the Cogging and 8/3 issue
""I can't find anything on the 8/3 anywhere. I own a CPC & CG-5 ASGT. I am looking for a larger mount and asking about the CGEM or DX series. I have seen this more than once but will post a copy of a post concerning the issue, this is the answer I got when asked about the 8/3 issue...
""It's a repeatable non correctable by PEC tracking error caused by the gears from what i understand.
That plus the motor cogging issue made me avoid the CGEM series (including the DX)even if i like them a lot as mounts.
If you give a look on the CGEM yahoogroup you will find a lot of information regarding both issues. ""

Will see what they say, and I knew Stargazer was sold on his DX ,
Kasey


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A. Viegas
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Reged: 03/05/12

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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6140608 - 10/16/13 10:29 AM

Kasey

One last bit of advice. If you can wait 6 to 12 months then wait. I suspect celestron will be unveiling a newer CGEM/DX that uses the motor technology of the VX soon. That newer mount probably does not have the 8/3 or cogging risks. Moreover I would not be surprised for a hybrid like alt-az/GEM like the new EQ8. So if you can hold out I would say wait a bit for the new upgrade.

If however you come across a good deal on the used market for a CGEM it may be worth it to upgrade. You can probably go Cgem for a net $500 after you sell your Cg5. So if you really want to jump to a bigger mount now then swap to he CgEM for $500 or so (used) and that probably works for you with the mallincam for the next couple of years. By then the newer celestron mounts will be fully vetted

Al


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fetoma
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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6140783 - 10/16/13 12:17 PM

Quote:

I suspect celestron will be unveiling a newer CGEM/DX that uses the motor technology of the VX soon. That newer mount probably does not have the 8/3 or cogging risks.




Al,

Where did you hear this information and is it from a reliable source?


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Steve Cobb
member


Reged: 04/26/10

Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6140982 - 10/16/13 02:00 PM

I've got the CGEM-DX and have had some trouble balancing the load and getting regular steady slewing -- there are pauses, noises, even failures to perform the slew. Usually it is okay but nothing's easy with this mount. Sorry to be so ignorant but what is a cogging or 8/3 problem or error?

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orlyandico
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Reged: 08/10/09

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Re: CGEM vs CGEM DX new [Re: Steve Cobb]
      #6141014 - 10/16/13 02:11 PM

Cogging - the DEC doesn't respond to small autoguiding corrections, then when the DEC pulses get large enough it jumps. This causes a sawtooth pattern in the DEC guiding graph. The cogging is caused by the cheap Igarashi motor whose armature doesn't have a cogless or reduced-cogging design.

8/3 - it is an irrational periodic error that occurs 8/3 = 2.6666.. times every worm cycle. Because it is irrational, it cannot be corrected with PEC. On some CGEMs and DXs the 8/3 is small, but on others such as the one I had (and Mark's/stew57's) it is huge. On mine it was over 20". With 20" of uncorrectable periodic error happening every 180 seconds, this means you are limited to about 30 seconds unguided with a short focal length (i.e. 400mm range).

Forget about Mallincam with a long-FL SCT as well, as Mark has discovered.

The 8/3 is caused by a harmonic in the cheap Igarashi gearbox used on both the CGEM and DX.

Bottom line, if you're lucky you'll get a decent CGEM or DX that doesn't exhibit cogging or 8/3. If you're unlucky you'll get both, and you'll get something that will bedevil the rest of your days with the mount. One big downside of buying used, is that the seller might be getting rid of it precisely because they're aware of these issues.

I sold my CGEM at a huge loss and I'm glad that boat anchor is gone. I sunk a lot of money and effort into it (Aeroquest high-precision RA worm, ADM dual saddle, replacement high-precision RA worm bearings, hypertuning, etc. etc.) but at the end of the day lipstick on a pig doesn't make it any less of a pig.

In fairness my CGEM pointed very accurately and was a dream to use for visual.

If I were the OP and I had $1500 or so to spend, I'd sit and wait for a used CGE to pop up. Made in the USA, Pittman Lo-Cog motors, same software as the CGEM, etc. etc. It is everything the CGEM and CGEM DX are not.


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fetoma
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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6142831 - 10/17/13 12:16 PM

Quote:

If I were the OP and I had $1500 or so to spend, I'd sit and wait for a used CGE to pop up. Made in the USA, Pittman Lo-Cog motors, same software as the CGEM, etc. etc. It is everything the CGEM and CGEM DX are not.




+1


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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: fetoma]
      #6142923 - 10/17/13 01:10 PM

is that the mount that was made by Losmandy before he left? I had heard he made some mounts for celestron, Kasey

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fetoma
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Reged: 09/26/06

Loc: Southern New Jersey
Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6143051 - 10/17/13 02:13 PM

Yes, it was the CI-700 I believe.

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Jason B
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Reged: 06/21/04

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Re: CGEM vs CGEM DX new [Re: fetoma]
      #6143084 - 10/17/13 02:30 PM

All I can say is that we have 3 CGEM/CGEM DX's in our astrophoto group/club and all have worked great for guided long exposure imaging (in focal lengths from 420mm to 2000mm). All are 3 years old or newer.

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DaveJ
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Re: CGEM vs CGEM DX new [Re: fetoma]
      #6143196 - 10/17/13 03:34 PM

Quote:

Yes, it was the CI-700 I believe.




Negative. Losmandy made the original G-11 for Celestron. It was branded "Celestron by Losmandy." I know this because I purchased a CG-11 the first year they became available in September 1992. The CI-700 was Celestron's attempt to duplicate the Losmandy-made G-11 after they (Celestron) decided not to pay for the G-11s any more. Losmandy never "left Celestron" since he didn't work there, Celestron contracted "Hollywood General Machine" to build the G-11 for them. Losmandy's big (now discontinued) GEM was named the "HGM" for Hollywood General Machine.


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DaveJ
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Re: CGEM vs CGEM DX new [Re: DaveJ]
      #6143232 - 10/17/13 03:59 PM Attachment (21 downloads)

Quote:

Losmandy made the original G-11 for Celestron.




It took me a couple minutes, but I found a photo of my 1992 Made-for-Celestron-by-Losmandy G-11


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A. Viegas
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Re: CGEM vs CGEM DX new [Re: fetoma]
      #6143468 - 10/17/13 06:27 PM

Hi Frank,


I am purely making a guess in my prediction that Celestron will incorporate the VX gear technology in its next version of CGEM/CGEM DX. I base my prediction on two facts.

1. At NEAF I spoke with Celestron people and I specifically commented on the gap between the VX and CGE-PRO and the issues with the CGEM. I asked them point-blank if they were going to upgrade the CGEM/DX and he said they were working on it. I was buying a CGEM at NEAF so I wanted to know the upgrade cycle. My understanding from the conversation was it 2014/15 at the latest.

2. Given the recent introduction of the EQ8 and Synta's involvement there, it seems logical to expect an entry in the Celestron line-up that will incorporate the concept of dual GEM/Alt-Az like the failed LX-80 and the new Ioptron dual GEM/Alt Az.

Nevertheless, I went ahead and got the CGEM and sold my CG5, because frankly I could not wait. But heck... we are probably 6 months closer now... So if I were in the OP shoes now, I would wait.

Al


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bogg
sage


Reged: 11/17/09

Loc: Bruce County Ontario
Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6143505 - 10/17/13 06:50 PM

Quote:

CGEM vs. CGEM DX is really a matter of cost and basically $500 when all is said and one, whether you buy new or used... What do you get for the extra $. Basically a better tripod, beefier counterweight bar and i suppose it's debatable if the motor control,board is better in th CGEM DX or not...

For a 9.25" the difference between CGEM or DX is probabl not worth $500... A 11" probably give the edge to the DX, I think 70% I would go with DX with 11"... A 8" is probably 70% better value on the plain CGEM and your 9.25" is more like 50/50 in terms of value proposition to the DX...

If you are planning to really upgrade in 3-5 yrs to an AP or Paramount, then I would say just get the CGEM and with resale value you probably do on... If on the other hand this next mount is close to your final mount purchase, then I would get the DX.

If you plan to guide, then the CGEM + DX are mostly comparable up to 2 mins... Given the savings I would say go for he CGEM ... I chose the CGEM because I bot it at NEAF, got a great deal and best of all saved enough,to buy more gear... I use it with my 8" and C80ED piggybacked...

Al




I was talking to a Celestron rep at ASTROCATS in Oakville earlier this year. I was asking what the difference was in the two mounts as I was thinking of putting it on a pier mount. The answer I got was I would be better off with the CGEM mount over the DX as on the pier it would have the same performance, including instrument weight as the DX. It really appears the only differences are the counterweight bar, the beefier tripod, and the mount connection between the head and the tripod. Mostly cosmetic. for some the better tripod would be worth it.


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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: bogg]
      #6143862 - 10/17/13 10:13 PM

Hey All, great news from Team Celestron,, I asked about cogging and 8/3 and heres the answer
""The so called "cogging" issue has been corrected in firmware. The public beta has been available for months. I haven't made that public yet becaue I had some checking I needed to do. But that should be done this week. And then I am going public with it.
As for the 8/3 term, as you said, it would require a new gear box like the one we have in the AVX. This might require changing the motor control board as well.""

I just replied back about possibly installing them myself if I ran into the 8/3 so will see. I asked about the cost for one to do it..... and did let him know that many LOVE their mounts and have no problems
Also Al, they do have the ability to dual mount, there is one that did it on this thread with pictures, and its in the knowledge base also,
Kasey


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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6143870 - 10/17/13 10:19 PM

A side note, I have my tri-pod from my CPC after I de-forked it.. I wish was a way to put like a pier mount on it... I am pretty sure is the same as the CPC 11 tri-pod. I am sure it could handle the weight easy, its pretty stout, Kasey

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orlyandico
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6143942 - 10/17/13 11:06 PM

You should be able to reuse the CPC tripod, with some machining. But the CGEM and DX are only sold with tripods, you don't save any money that way. But really why not the tried-and-true Atlas, which has no 8/3.

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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6144308 - 10/18/13 06:50 AM

the Atlas is only rated to 44lbs and is $300.00 more and has to be polar aligned? Also from all I have seen Celestron has very very good customer support. I know the Atlas gets good reviews,
Kasey


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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6144404 - 10/18/13 08:43 AM

There is EQMod and they have an ASPA like procedure.

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orlyandico
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6144422 - 10/18/13 08:47 AM

I would take those weight ratings with large chunks of salt. In my opinion a +/- 5 lb difference with these mounts is immaterial.

Does anyone really believe the iEQ45 is 45 lb rated? If you've handled it, compared to the Atlas and CGEM it is much more lightly built - and not in a good way. The Mach1 weighs less than the Atlas or CGEM but nobody would mistake it for being less beefy.

The Atlas now has an ASPA procedure as Mark pointed out (it's made by the same company that makes the CGEM!) and the Atlas doesn't have cogging or 8/3.

But then I'm biased, having owned a CGEM for a long time. I dance on its grave.


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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6144539 - 10/18/13 09:59 AM

LOL on dancing on the grave Orlyandico,, I have another post on Team Celestron adressing 8/3, will see... Also Celestron has 2 year warranty and Orion only 1 year,, is another consideration..... Even looking at Losamndy G-11, Kasey

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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6144548 - 10/18/13 10:03 AM

Also the Arizona ASAE show is coming up in Nov. msy go to that and get a good deal on something like Al ,
Kasey


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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6144555 - 10/18/13 10:08 AM

The G11 is in another class. Celestron will warranty their mount well. It took 6 to 8 weeks from the time I shipped the mount to them until I got it back. They will exchange it if they feel it is a difficult dagnosis. It took 4 tries for me.

An update to integer motors will move this mount up a class. I run mine with 40+ lbs at times. At shorter FL or shorter exposures (under 2 or 3 minutes) it will guide fine. The software is the best around.

If I had to do again I would have gone with the Atlas. As it is I am waiting for a US release of the EQ8 or a CGEM update.


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dragonslayer1
scholastic sledgehammer


Reged: 02/25/12

Loc: SLC, UT
Re: CGEM vs CGEM DX new [Re: Stew57]
      #6145167 - 10/18/13 04:17 PM

Hey Mark, I think the EQ8 in US dollars is about $4,200? Am just curious if thats right why you would not look at a Losamndy G-11/G-2 for almost 1K less? Also my post in T/C for cogging and 8/3 is under the Misc link if you want to see what they say..
Kasey


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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6145314 - 10/18/13 05:50 PM

50kg capacity, lower PE, EQMod, and second set of incoders that keep position.

If you are looking for any long intigration doing astrovideo unguided, forget thre CGEM\DX. In PM with those at Celestron, I was told that was a 1 percent user loking for that quality, and they did not have the resources to pursue a fix for the 8/3 error. I was told about a year ago by one that there was going to be some exciting news for me, then the AVX was released. I thought the same integer servos would be used in the CGEM/DX but then in pm have been told to not count on it any time soon.

Many swear by the CGEM, but they are either visual or guided at usually shorter FL.


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rmollise
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6145336 - 10/18/13 06:08 PM

Quote:



If you are looking for any long intigration doing astrovideo unguided,




Not the case at all. Period. Plenty of people are doing just that.


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Stew57
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Re: CGEM vs CGEM DX new [Re: rmollise]
      #6145377 - 10/18/13 06:32 PM

I have watched NSN and asked around and have found very few. I have tried my self with a couple of CGEMs. 2 min unguided at long FL is a dream for a CGEM. Video is forgiving but not that forgiving. If you have some raw screen shots I would love to see them.

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A. Viegas
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6145510 - 10/18/13 07:56 PM

My CGEM can go about a minute at 1000 mm FL unguided, if my polar alignment is decent. I have not tried higher FL nor more exposure time unless I am guiding. I do not have any delusions with the CGEM, if you want to go over a minute unguided you probably have to be 600-800mm FL and using a lightweight (like under 20 pounds) scope. HOWEVER, if you are guiding, then you can easily get 3-4 minute guided exposures which for video is plenty at 1000mm FL. I have not really tried more, but if I get clear skies I will try at 2000mm FL and see what I can get.

Al


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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6145702 - 10/18/13 10:07 PM

Ok am a C 9.25, MR-5 W 10mm spacer, so what,mmmm about 4.5 f/r off the top of my head.. Whaat was really hoping to do was be able to get 2 min unguided and decent video pics,,, some say is easily possible and are doing it,,, may be they are the lucky ones and got their mount off a good line or batch... I know you Mark have had real fits with yours it seems,, 8/3 and cogging.....They have addressed the cogging with latest firm ware per Derik,,, I have an open question to him about the 8/3 so will see on that... I am snooping in the Losmandy G-11 threads and asking questions also,,, This has to be my last mount so want to do it right and not break the bank, but do not want to overshop or overbuy as they say,,,, Have an Orion ST 80 mm to piggyback, and if ever go bigger on OTA would be 10" R/C? or C11 max
Kasey


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6145703 - 10/18/13 10:08 PM

RATS forgot to add, would be curious how much unguided you can get Al,, thank you, Kasey

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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6145713 - 10/18/13 10:15 PM

I will experiment tomorrow night if I get clear skies.

Al


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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6145729 - 10/18/13 10:25 PM

Thank you Al, my time is limited for viewing and it seeems lately everytime I have the chance the weather is the pits,,, and now is a full moon,,, LOL, Kasey

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6145738 - 10/18/13 10:28 PM

Quote:

I have watched NSN and asked around and have found very few. I have tried my self with a couple of CGEMs. 2 min unguided at long FL is a dream for a CGEM. Video is forgiving but not that forgiving. If you have some raw screen shots I would love to see them.




Our experiences differ. Anyhow, the CGEM's unguided performance is very comparable to the other mounts in its price range AND to those in the tier above including the G11.


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Re: CGEM vs CGEM DX new [Re: rmollise]
      #6145778 - 10/18/13 10:50 PM

Thank you Rod, and you are probably already aware of them possibly addressing the 8/3, but I have a question on it posted on Team Celestron Misc web page... I seems that the 8/3 is maybe hit and miss or real mild and a few can be real severe,,, guess is the luck of the draw,,,,,I guess if you get a bad one cn always exchange it,,,
Thank you, Kasey


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Re: CGEM vs CGEM DX new [Re: rmollise]
      #6145785 - 10/18/13 10:54 PM

Raw PE of the competing mounts are all similar which would be the limiting factor in uunguided use. To reduce this inherent problem PEC is used. The 8/3 error in the CGEM/DX, depending upon the severity of the error, makes the PEC on the CGEM work less optimally than the others, Iin fact in some cases depending on the PE curve and 8/3 error, PEC can make things worse. When unguided quality PEC is invaluable, and may not be working on a lot of CGEMs. None of this matters for guiding.

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6145949 - 10/19/13 01:00 AM

I'm not sure if a large 8/3 is considered grounds for return. I had similar PM's with Derik, he said that the 8/3 is under 8" p-p for most people (but for me it was over 20" p-p) and that only 1% of imagers needed that performance. Same story as Mark.

If you can buy the CGEM or DX at a local store, and be able to return it if you get one with huge 8/3 (spare yourself the shipping headaches) then I'd say it's worth the risk.

Otherwise, the Atlas is a safer bet. As Rod points out, all of these mounts have comparable periodic error. The difference is, the 8/3 can't be corrected by PEC, so long-duration unguided is out. An Atlas with a good PEC training should be able to get under 5" corrected. Very few CGEM's would be able to achieve that (even Derik's best case of 8" of 8/3 means you can't get less than 8" after PEC).


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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6146160 - 10/19/13 07:57 AM

Man oh man, decisions, things to digest, ponder weight capabilities, craving 2 minute unguided (I like the Alt/AZ of Atlas and CGEM & DX).. It seems from what I could gather that the servo motors seem like would be better just for normal viewing, tracking, not considering guiding into the formula. I gather that they have a constant source of "power" applied to the motors?? But yet Atlas always seems to get good reviews... I just wish it was rated for more weight (6lb), alt/az could almost be a c-6,,, I know Celestron has excellent customer service, how is Orion? Then have 1 year warranty vs 2 year.. And Celestron just seems to be trying new things, Kasey

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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6146196 - 10/19/13 08:26 AM

If it is of help i was on the same dilemma you are now, i waited as long as i could for a solution for the CGEM...and i finally found it on the new AZEQ6...I never looked back and i'm really happy with the results.
PS: I do guided immaging , and i have far better results than the CG5 CG5 even with guiding.
In the past i used to do unguided 1 minute exposures at 945mm and 1500mm with the CG5)
Here is an example with the cg5 at 1500mm unguided


I can't immagine why the Atlas or the Atlas AZ can'd do any better,specially at lower focal lenghts.

Edited by Mike X. (10/19/13 08:39 AM)


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6146217 - 10/19/13 08:40 AM

Quote:

Thank you Rod, and you are probably already aware of them possibly addressing the 8/3, but I have a question on it posted on Team Celestron Misc web page... I seems that the 8/3 is maybe hit and miss or real mild and a few can be real severe,,, guess is the luck of the draw,,,,,I guess if you get a bad one cn always exchange it,,,
Thank you, Kasey




I would spend exactly zero time worrying about "8/3," especially if I were doing video.


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Re: CGEM vs CGEM DX new [Re: rmollise]
      #6146220 - 10/19/13 08:46 AM

Video?!? Wow sorry i must have missread, i agree with Rod,no need to worry about that then, choose the mount you like most

Edited by Mike X. (10/19/13 08:46 AM)


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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6146258 - 10/19/13 09:14 AM

Quote:

The G11 is in another class.




And another complete class of issues. Research well before you drop your coin on one.

Phil


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Re: CGEM vs CGEM DX new [Re: Phil Cowell]
      #6146285 - 10/19/13 09:40 AM

Thank you all, yes am seeing the G-11 is another class/world it seems. Nice pic Mike; yes am doing video now but started out DSLR on a 4SE/ then CPC9.25/ then some minor CCD,,, I would like to try some more down the road, just at this time my time is limited somewhat and video offers the best option for viewing under time constraints, (even if not under constraints is a real gas), Kasey,,

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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6146290 - 10/19/13 09:41 AM

PS now am using C9.25 on CG-5; this is to be travel mount,
Kasey


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6146326 - 10/19/13 10:10 AM

It is true that in the past those doing astrovideo had lower expectations. It seems that they are becoming more demanding. The chip does not care if it is in a dedicated ccd camera or a video camera. The error is the same.

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6146363 - 10/19/13 10:30 AM

The G11 is just fine. It probably has as many issues from people tinkering with it as legitimate problems. Somewhat similar to a CGEM. The new G11s certainly don't have the work gear issues like the old ones. There was a bad batch in 2012.

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6146699 - 10/19/13 01:21 PM

Quote:

It is true that in the past those doing astrovideo had lower expectations. It seems that they are becoming more demanding. The chip does not care if it is in a dedicated ccd camera or a video camera. The error is the same.




Most video users are still not doing long exposures, however--it's not necessary--and most CGEM users have had better luck with their mounts than you have. I'm sorry you have had trouble, but, frankly, you experience is not typical.


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6146902 - 10/19/13 03:29 PM

The servos in the CGEM and DX are pulse driven. They are operated like steppers that use encoders rather than count steps. The advantage you list for servos does not exist for the CGEM\DX.

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6146919 - 10/19/13 03:40 PM

OK, so trying to see if I understand this right, if they were "servo" driven, there would not be a pulse but more like a potentiometer or reostat controlling a steady source of voltage or current?? The "encoders" would have to be changed to run them like servos rather thanpulse driven?? Am I even close to getting it??? , Kasey

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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6147059 - 10/19/13 05:08 PM

If you are polar aligned only the RA would be driven. There would be a constant current only varied as the encoder relied being ahead or behind the correct position. The servos in the CGEM are given pulses of curret that drive the RA. There is nothing wrong being pulse driven. Servos being better than high resolution steppers is a red herring in my opinion.

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6147657 - 10/19/13 11:43 PM

No, no, no.. all servo motors are driven using PWM (pulse wide modulation). Nobody drives servos with constant current, it would be too inefficient.

Servos still have advantages over steppers - more torque at low speeds (no need to micro-step) and a larger dynamic range, i.e. they can run at both low speeds and high speeds very well. With steppers you have to decide whether you want very fine low-speed performance (in which case the maximum speed is compromised).

That said, a not-so-good servo implementation results in... cogging.

Kasey, you are over-analyzing this. As Rod has said, there isn't much difference between all the mounts in this class. And your concern about the Atlas having 6lb less capacity? that's irrelevant. The weight ratings Celestron and Orion throw out are optimistic anyway. I would go with the Atlas, for reasons already previously stated.


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6147986 - 10/20/13 08:23 AM

Kasey-

So early this morning I tried using my C8 on the CGEM with my Mallincam Extreme and I did not guide. Conclusion is you can probably get 60s - 90s without too much trouble if you bother to decently polar align. My PEC training apparently sucks because it messed up a few of the pics, so maybe if you are not a total doob like me and you can figure out PEC maybe that gets to about 2mins?

For my test run I ran the following:

CGEM with 1 17# and 1 11# counterweight
C8 with C80ED refractor piggybacked + 50mm finder +MCX and Orion SSPIAG guider. So probably 27 # I am guessing total weight.

There was a full moon and I did not use any filters. For the Mallincam I used ONLY the MFR3 rear element which according to my astro-aid APP and Astrometry.net is basically F8 so ~1600mm FL - a decent test I think.

Ok here are the images. Easy one first

M42 - MCX in CCD Mode (NO AGC) - C8 @ F8 --35 seconds

[image]http://www.cloudynights.com/photopost/showphoto.php?photo=28474&password=&sort=7&thecat=500[/image]


M42 - MCX in CCD Mode (NO AGC) - C8 @ F8 --50 seconds

[image]http://www.cloudynights.com/photopost/showphoto.php?photo=28473&password=&sort=7&thecat=500[/image]

NGC1514 - MCX in CCD Mode (NO AGC) - C8 @ F8 --90 seconds

[image]http://www.cloudynights.com/photopost/showphoto.php?photo=28472&password=&sort=7&thecat=500[/image]

-Note this last one was close to the moon and i found out later a leaf had fallen on the corrector making that mark in the upper right corner.

As you can see at 90 seconds I was starting to get trailing.

--Hope this helps

Al


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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6148050 - 10/20/13 09:17 AM

I stand corrected. Thanks
There is one advantage to a stepper often over looked. When overloaded a stepper will just sit and try and step with no ill efects. The servor will draw more current until something spills it's magic blue smoke, unless there is some type of overload protection built in the circuit.


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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6148084 - 10/20/13 09:39 AM

I stand corrected. Thanks
There is one advantage to a stepper often over looked. When overloaded a stepper will just sit and try and step with no ill efects. The servor will draw more current until something spills it's magic blue smoke.


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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6148145 - 10/20/13 10:19 AM

Quote:

Kasey-

So early this morning I tried using my C8 on the CGEM with my Mallincam Extreme and I did not guide. Conclusion is you can probably get 60s - 90s without too much trouble if you bother to decently polar align.




Let me add that 60 - 90-seconds with a very sensitive Mallincam is about the maximum exposure for most peoples' skies. My most used exposure with the Mallincam Xtreme is 14-seconds, and my max is usually 30, and this is from fairly dark sites including the Chiefland Astronomy Village...

Also, most video users are not obsessed with pretty pictures. We want to go deep and see lots of detail, and off-round stars once in a while are simply not a big deal for most of us.

Take your pick, CGEM or Atlas; both will do just fine. You may find the Celestron's hand control and alignment system easier to use, however.


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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6148158 - 10/20/13 10:28 AM

Quote:

I stand corrected. Thanks
There is one advantage to a stepper often over looked. When overloaded a stepper will just sit and try and step with no ill efects. The servor will draw more current until something spills it's magic blue smoke.




Or a plastic gear which i believe the celestron motors actually have.At least the cg5 ones do.
So when it comes to a situation like this, if we are lucky enough the gear will break before the motor rests in peace.

Edited by Mike X. (10/20/13 10:32 AM)


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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6148170 - 10/20/13 10:34 AM

Hey Al,
Thank you very very very much for the time and effort you put forth in doing that. I was wondering if it could be slightly off on polar align?? The trails or egg shapes look pretty consistent (have no clue what cogging or 8/3 error would look like ),, and just a heads up.. I have a question to Team Celestron on the cogging and 8/3. Derick answered the cogging and says they have a firmware fix ready to roll out to fix it. The 8/3 no answer yet but from all I gather not too sure that will be addressed in the near future as probably will require motor/gear change...
I don't think the 8/3 can be fixed with PEC from what I can gather from people above my pay grade. You might want to check that answer in T/C I posted on cogging tho and get the firmware fix.... One thing is for sure, if they do address the 8/3 their will be a 99.999999% chance there will be an upgrade for older mounts ,,, Thank you so much again Al, is much appreciated,
Kasey


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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6148180 - 10/20/13 10:38 AM

Thank you Mark,
I think with your patience I am finally able to wrap my head around the stepper/servo issue.. That really makes sense now . Thank you, Kasey


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6151903 - 10/22/13 03:35 PM

A FYI from Derik on CGEM vs CGEM-DX motors, electronics, gears , etc.
""It used to be that the CGEM and the CGEM had different electronics. But as of some time last year, all CGEM's have the updated electronics. So nowadays, the biggest differences is the Tripod, and the longer clutch knobs.""'
Kasey


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6151923 - 10/22/13 03:44 PM

Quote:

A FYI from Derik on CGEM vs CGEM-DX motors, electronics, gears , etc.
"It used to be that the CGEM and the CGEM had different electronics. But as of some time last year, all CGEM's have the updated electronics. So nowadays, the biggest differences is the Tripod, and the longer clutch knobs."




Plus a much longer, thicker & heavier counterweight shaft (1.25" diameter vs what, 3/4" or 7/8"?) and heavier counterweights.


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Re: CGEM vs CGEM DX new [Re: DaveJ]
      #6151976 - 10/22/13 04:10 PM

Yes and now trying to decide on DX or just CGEM???? Right now using a C 9.25 & have Orion ST SSAG and crayford & VSS+/ probably max weight 30#, right now using it on a CG-5 (this is to be my travel mount). Could possibly see getting a VRC @ about 18# down the road... Right now doing Video but don't want to not be able to do DSLR or CCD as I have in the past,,,, so not wanting overkill, but wanting enough ,,, Kasey

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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6152003 - 10/22/13 04:30 PM

Kasey,here is my 2 cents for what they worth.

Consider also the weight of the mount.
If you are going to use the CGEM DX permanently mounted, that's ok, but if you are going to assemble it and dissasemble it every time....hmm i think it's a beast.

I believe for video astronomy the CGEM or the NEQ6/AZEQ6 are more than enough for your C9.

Edited by Mike X. (10/22/13 04:32 PM)


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Re: CGEM vs CGEM DX new [Re: Mike X.]
      #6152058 - 10/22/13 05:05 PM

Thannk you Mike,
I would use the JMI wheely bar I have. I bought it when I was using my CPC, it really is nice. From all I can gather sense last year they are identical x-cept the diameter of tri-pod legs. I have read some of the other brand mounts that that is a complaint, weak legs. I don't think Celestron has had that problem,, Kasey


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6152106 - 10/22/13 05:45 PM

I routinely set up and break down my CGEM DX. IMO it's not that much of a beast to deal with, really. There's a reason that the tripod, mount, and counterweight shaft come apart and are manageable weights.

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Re: CGEM vs CGEM DX new [Re: dpippel]
      #6152110 - 10/22/13 05:48 PM

I can carry my CGEM with the mount already on the tripod out as a single unit. I add weights then ota. Doubt I could carry the DX tripod with the head already mounted. Would make another trip and having to mount the head on the tripod.

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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6152167 - 10/22/13 06:20 PM

Here is a solution that worked for me: http://www.scoperoller.com/casters.shtml

Though I don't see a CGEM DX set listed, unless the Celestron HD tripod he calls out is the right one. If it looks like a potential solution for you you could contact him. I've talked with him and he's pretty flexible.


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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6152220 - 10/22/13 06:43 PM

Quote:

I can carry my CGEM with the mount already on the tripod out as a single unit. I add weights then ota. Doubt I could carry the DX tripod with the head already mounted. Would make another trip and having to mount the head on the tripod.





Yep I do the exact same thing. And yeah the DX tripod is a LOT heavier. I would break it down if I had a DX, but it is still manageable.


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Re: CGEM vs CGEM DX new [Re: mich_al]
      #6152231 - 10/22/13 06:47 PM

Thats what I like about the Jmi Wheelybar, its a tripod looking thing and I put some boards across the bottom so have a small tray thats good for accessories etc, just wheel it out with all in one swoop,, but I view from my driveway.. They do make some for rough terrain tho.
Mark, can I ask what you run on your CGEM as far as weight?
Kasey


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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6152256 - 10/22/13 06:59 PM

From a light weight AT6RC to a C11hd with Celestron guidescope 2 mallincams and meade dsipro.


http://i906.photobucket.com/albums/ac263/mstew57/SSA%20mounter%20to%20CGEM/P1...


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orlyandico
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6152601 - 10/22/13 10:22 PM

i think hoping to use a DSLR (which implies long exposures) with a C9 on a CGEM is.. optimistic. You would definitely need to guide, and even then would probably be bedeviled by oblong stars. 2350mm is long.

I have a C9 and had a CGEM. The few times I tried prime focus with the C9 on the CGEM, even with guiding, the results weren't pretty.


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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6152622 - 10/22/13 10:35 PM

No wonder I coiuld not find my thank-you/ posted it in wrong forum LOL...

""Well I pulled the trigger and went with the CGEM,,,,, and yes, ordered SS also I know still has kinks but will be resolved... I want to thank everyone for their time input experience expertise insights etc. ,, Will post a couple pics and see what its capable of unguided,, hopefully have a very good line number ,, Once again, thank you all,,
Kasey""


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Stew57
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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6152658 - 10/22/13 10:53 PM

Live video is more forgiving but yes guiding will be a must at those FL, unless you like a lot of comets in your images.

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PhilCo126
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6152942 - 10/23/13 04:32 AM

Worked with a brand new CGEM for 4 years and never had an issue... Upgraded to a CGE to carry my 18 kilograms of refractors

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Stargazer78
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Re: CGEM vs CGEM DX new [Re: PhilCo126]
      #6153046 - 10/23/13 07:02 AM

The DX is alot heavier than the cgem mainly because of the tripod. Not to toot my own horn but I work out regulary and have entered in a few strong man competition's and it takes me a total of 4 trips to set it up. Tripod , mount, counter weight bar and counter weight, and finally OTA. So with you getting the CGEM it would be alot more manageable setting up. I beleive it has the cg5 tripod or something that is very similar. I will also recomnend you spend some time and learn to drift align. I do the ccd method and its very easy to do. If you remember a few posts of mine when I first got my mount I was convinced I had the cogging issues and what not. But in the end my polar alignment was the culprit. I hope you enjoy your new mount as much as I do and I cant wait to see what images you get with your setup!! Congrats on the new mount my friend!!!!!

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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: Stargazer78]
      #6153103 - 10/23/13 08:12 AM

Yes I remember your "Cogging issue" and learned from your experience, polar align well ,, will post a couple pics unguided to see what it can do and thanks for your input and experience..
Kasey


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Mike X.
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6153115 - 10/23/13 08:23 AM

Congrats on the new mount!

PS:I agree with Stargazer regarding the DX non DX and weight.
I can understand the DX can be broken to parts and be "trasportable" but i guess this is an issue that can be interpreted in very different ways because any of us has very different habbits and needs.

When i manage to photograph during summer, i have to assemble and dissasseble the mount every night for about 20 nigths,and transport it also on foot.
Every night is about 4 trips back n forth between OTAS,Mount head, counterweight etc..so at least from my point of view..having to carry such a heavy mount and tripod can be a pain.

Edited by Mike X. (10/23/13 08:25 AM)


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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6153235 - 10/23/13 09:28 AM

Here are 4 unguided 2min exposure video captures. They show the variation in tracking for one complete worm rotation. Remember where you are on the worm will make a difference in how your exposure turns out. You can see that the polar alignment (pic 3) is not too bad (used ASPA). PEC is off. I tried a couple of runs and these were the best tracking of the bunch. DEC is horizontal direction in these photos. There was no wind at all.

http://s906.photobucket.com/user/mstew57/library/CGEM/CGEM%20tests?sort=3&...

I should add these are with the C11 at F10. 2800mm FL

Edited by Stew57 (10/23/13 09:31 AM)


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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6153270 - 10/23/13 09:50 AM

Hey Mark, number 3 is not really bad @ 2800mm, 2 minutes and that weight.. They say any mount at 2300+ is hrad to get good pics unguided for any length of time... looking forward to testing mine. Now looking into travel scope for the CG-5, thinking c8 or c6, I also hope all is going well with your tools replacement and ins, Kasey

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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6153364 - 10/23/13 10:28 AM

Yew but it may take 8 minutes or more to get that shot. Way too long for outreach. That is the reason I was wanting the 8/3 fix. I have tried the PEC but with my larger 8/3 error it does not help. I have run the AT6RC unguided and the C11 with a MFR5 unguided (about the same FL) and the tracking difference is negligible. Of course the reduced FL makes a huge difference.

As far as the tools I have some borrowed to keep work going and am dealing with the insurance. Who keeps tool receipts especially for 40 years?


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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6154885 - 10/24/13 06:52 AM

A while back there was a thread about putting either a plastic milk jug piece or this "slick strips UHMW" between base and head to make polar align RA adjustments easier.. My CG-5 there is only a small area that rides on the reciever base, for the CGEM series is the base riding area much wider? Am waiting for mine to arrive but did order some of the UHMW strips to cover the necessary part, Kasey

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orlyandico
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6154918 - 10/24/13 07:35 AM

The area is wider but it's not that flat, so the entire surface isn't used. The UHMW will definitely help.

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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: orlyandico]
      #6155035 - 10/24/13 09:03 AM

thank you, did you ever do it on yours? and do you tape the base (Tripod) or base of mount for best application?
Kasey


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DaveJ
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6155036 - 10/24/13 09:04 AM

Quote:

A while back there was a thread about putting either a plastic milk jug piece or this "slick strips UHMW" between base and head to make polar align RA adjustments easier.. My CG-5 there is only a small area that rides on the reciever base, for the CGEM series is the base riding area much wider? Am waiting for mine to arrive but did order some of the UHMW strips to cover the necessary part, Kasey




I hate to nit-pick, but it's not an "RA adjustment" but rather an "azimuth adjustment." Correction provided to keep newbs from being confused.


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Stew57
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Re: CGEM vs CGEM DX new [Re: DaveJ]
      #6155046 - 10/24/13 09:08 AM

I use the good old milk jug. My mount is kept tightly mounted, never removed. The Az adjustment is silky smooth. The threads are rather coarse but you will get used to it.

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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: DaveJ]
      #6155048 - 10/24/13 09:09 AM

duly noted and you are spot on, thank you for correction, was brain freeze on correct term when posting , Kasey

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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6159143 - 10/26/13 12:56 PM

Ok heres a brain freeze,, I got my mount last night (CGEM) but I did not get a dovetail for my 9.25 to fit the saddle....... Well I got to play with the polar scope and using it and seems pretty neat.... Anyway, ordered a dovetail but till it gets here I rigged up a saddle fit for my 9.25 dovetail to work (involves spacers, safteywire etc..) and is solid...
Now the deliema (possibly) powered it up and setting up handset it asks for align marks on AZ & DEC,,, Well I have my OTA 180* out if align dec marks.. it is facing down instead of up and north..... The question is, if I callit aligned even being 180* out, will the mount or handset know it????
I can swap ends on the OTA but is a real pain with the spacers and way I have it mounted... Do you think it will know the OTA is facing North with align marks 180* out when I say yes , align marks are lined up???
Hope this makes sense,,, Kasey


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dmdouglass
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6159303 - 10/26/13 02:31 PM

dragonslayer1.....
I am sending you a private mail. hopefully you are set up to receive it.


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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6160054 - 10/27/13 12:45 AM

have it all working now and just loving my CGEM, taking 60 sec unguided and looking good so far,,, man oh man, what a mount,,, David got your PM, is all good, will talk tomorrow if is ok with you, Kasey

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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6160617 - 10/27/13 11:53 AM Attachment (7 downloads)

A pic for ref

Edited by dragonslayer1 (10/27/13 11:56 AM)


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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6160626 - 10/27/13 12:00 PM Attachment (8 downloads)

the first pic 120 sec unguided, and this one 60 sec unguided, Pictures are not for sale LOL,,, they just show tracking, the pics suck, Kasey

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dpippel
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6160633 - 10/27/13 12:02 PM

Is that the Dumbell hiding in there?

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dragonslayer1
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Reged: 02/25/12

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Re: CGEM vs CGEM DX new [Re: dpippel]
      #6160656 - 10/27/13 12:15 PM

Yes M76 the little one, the settings on my camera need work, was mostly to test tracking, I struggle at this picture taking, Kasey

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A. Viegas
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6161548 - 10/27/13 09:46 PM

Kasey,

Congrats on the tracking, Your focus seems off, also I think you may have some dust on your camera or reducer

Al


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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6161592 - 10/27/13 10:21 PM

Hey AL, Yeah I need to start from scratch, collimation etc,,, plus every neighbor had every interior and exterior light on last night,,, but the mount is sweet... Oh yes, when the full moon comes up they turn them off LOL... Have you downloaded thay fimware (31.13?) from team celestron for cogging I think? I tried but my computer tries to open with I-tunes... Have to figure that out. Thank you again for all your help, Kasey And will dust things off

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Stew57
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Re: CGEM vs CGEM DX new [Re: dragonslayer1]
      #6161644 - 10/27/13 11:00 PM

If you don't have cogging problems with the DEC axis there is no need to update the firmware.

I should say there is no reason to run a beta firmware.

Edited by Stew57 (10/28/13 01:28 AM)


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A. Viegas
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6161954 - 10/28/13 07:39 AM

derik at team celestron is close to making the latest beta a final release so I would just wait on that upgrade. I am using the version right before 31.13 or something and honestly have not run PEC or PEMPRO yet to see if it improves... I always guide so not much of a need anyhow as with the mallincam it's rare to need to go over 3 min exposures

Al


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Stew57
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Re: CGEM vs CGEM DX new [Re: A. Viegas]
      #6161972 - 10/28/13 07:52 AM

The firmware was designed to solve the DEC cogging issue that only showed up when trying to guide. If your mount guides fine you don't need it.

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dragonslayer1
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Re: CGEM vs CGEM DX new [Re: Stew57]
      #6162315 - 10/28/13 11:37 AM

Thank you Al and Mark,
Well could never get it to work so never updated. I am really behind the power curve on computers; I told my wife that these guys are really intelligent, they cover everything from computers, electronics, physycs, math, astronomy, photography, etc etc..
I did have a rare expereince tho, first night after getting mount had 1 night of good viewing..... I beat the storm by one day LOL...
Kasey


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