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CGEM DX Hypertune Time lapse & Full write up

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#1 DaemonGPF

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Posted 08 July 2013 - 11:36 PM

My write up, time lapse, and annotation on rebuilding my CGEM DX mount.

I put it all together on my blog since it was easier to format and source images and my time lapse. Hope this helps.

PLEASE ask anything about this topic if you want clarity added to any part of it. This was my 4th mount rebuild, 3 of which were Celestron mounts. If you're considering rebuilding yours for similar reasons, by all means, ask anything and I'll do my best to explain.

The time lapse portion of the video is more to show the time and effort investment in doing a full overhaul, the segment after with the notations is more practical, along with the still images on the blog and attached gallery.

Feedback appreciated. I put a lot into capturing this as best as I could, including what I used, what I did, why I did it.

Time lapse was 4000+ exposures.

#2 Laz

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Posted 08 July 2013 - 11:52 PM

absolutely fantastic video, so much for quality control, wonder what the Chinese workers make per hour building these. Reason I am keeping my old super polaris mount !

#3 frito

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Posted 09 July 2013 - 12:29 AM

great job Josh, makes me want to do the same to my CG-5

#4 CounterWeight

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Posted 09 July 2013 - 01:15 AM

Great work there Josh soup to nuts! Interesting design used, better QA and assembly specs would make a huge difference it seems. thanks very much for this great documentary.

#5 InIt4TheImaging

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Posted 09 July 2013 - 03:02 AM

Very nice Josh.
I´m sure it will be alot of help for others in your situation.
...and I´ll bet the guys at Celestron are thrilled too :whistle:

#6 terry59

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Posted 09 July 2013 - 05:01 AM

That is an excellent capture of the process Josh. I have to wonder about all of the Chinese mounts!

#7 shrevestan

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Posted 09 July 2013 - 05:44 AM

Great write up! Looking forward to the test run!

#8 Madratter

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Posted 09 July 2013 - 10:09 AM

Wow. Someone really botched the first go around.

#9 shrevestan

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Posted 09 July 2013 - 10:40 AM

A lot of your issues sound familiar with my mount. Sporadic declination drift, lots of play in the gears, random jumps while guiding. I'll have to read through your writeup a few more times before I get brave enough to work on mine. I'm not very mechanically inclined at all.

#10 shawnhar

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Posted 09 July 2013 - 11:20 AM

WOW, that's dedication! Mine would never work again were I to dismantle it like that! :bow:

#11 DaemonGPF

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Posted 09 July 2013 - 11:35 AM

Thanks guys. I think this is definitely going to be a great discussion for several.

Let me say this much - I really do like features in Celestron mounts, so I'm not trying to make this a bashing session in any way. All Star Polar Alignment is fantastic for those who set up and tear down every night. The hand controller is very intuitive. They carry aesthetically pleasing looks (not that it's really important).

However, I fought with my CG-5 for months due to the same reasons and had to gut it and overhaul it. My Nexstar 8 GPS was the same. After reworking them, they behaved as they should. I had one regular CGEM that I didn't have to do a thing to. Wishing I had kept that one now. Point to this is that in each case there were clear signs of QA problems, and "drive through" servicing apparent by the markings inside on various components. Granted, the CG-5 is a $500ish mount new, and a DX on the upper end of the aforementioned is $2000ish - none of which are what I would call "high end" gear by any stretch of the imagination. But, one can't sit and advertise these things at their given capacities and mark them as astrophoto capable and keep an honest smile. It's sad in my humble opinion because the issues I keep seeing are minor things that could easily be remedied with just some QA improvement and modest adjustment to manufacturing.

If anyone starting out in AP wonders why people spend $5,000-$50,000 on mounts - it's usually to avoid these types of problems. Granted not all of us have that kind of disposable income(my wife would kill me if I tried to blow $10K on a mount), thus this bracket of the market exists. However, one should not expect magic straight out of the box. If you're serious but on a budget, you may want to consider the fact that you might have to roll up your sleeves and get a little dirty. Think of it like building a tuner/project car. You can get your money out of one of these mounts. If you look in my image galleries over the years you can see I ultimately ended up with equipment that would track just fine within their capacity limitations. By that I mean focal length as well as actual weight.

I could have easily ignored what I saw on this DX mount and simply shot widefield at 400mm and less and probably be quite content. However, I want to shoot at longer focal lengths occasionally and this was not remotely going to happen with the existing state of the mount. They sell this thing with a C14 as astrophoto capable! I'm trying with a C8 at under half the weight and half the native focal length and couldn't get it done at first. That's just not right.

I think after I get my first light results post-hypertune, I might write up my findings a bit more formally and shoot this over to Celestron. Might not make a difference, but at least I can say I tried.

I guess it's safe to say my warranty is gone on this. Was it worth it? Yep. Definitely.

#12 terry59

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Posted 09 July 2013 - 12:25 PM

Josh - You hit on a few things that just resonated with me big time. These (and I dont just mean Celestron) are touted as AP mounts yet can have serious deficiencies that occur during manufacturing. Returning it to the distributor is a gamble and it will not be serviced the way you did or someone like Ed would, but doing that voids the warranty.

Sounds like a "mad as hell and not going to take it any more" scenario to me :flame:

#13 shrevestan

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Posted 09 July 2013 - 12:34 PM

Yeah,the DX is the first and only mount I've ever purchased. Given the pricetag and advertisements, I knew I wasn't getting the top of the line, but figured I would at least get something that worked with no major issues out of the box.

#14 Madratter

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Posted 09 July 2013 - 12:34 PM

What is surprising to me is that I get the impression my CG-5 (which I decided was not good enough for AP with a C-8) was better than your CGEM-DX at least with a C-8 on it. There is something seriously not right about that situation.

I have to admit that I love the Celestron hand controller, and Nexremote was a good thing. But when it came time to upgrade, all the bad press about DEC cogging and such steered me well clear of Celestron. I know it ultimately does not hit them in the pocketbook since I went with an Atlas which is also Synta. With EQMOD I don't miss the hand controller either.

#15 BlackBirdCD

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Posted 09 July 2013 - 12:58 PM

Great article and thank you for sharing. As someone who is looking to get serious about AP, I find this sort of material extremely helpful. And I don't mind rolling up my sleeves to get things in proper order.

#16 DaemonGPF

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Posted 09 July 2013 - 01:46 PM

Yeah,the DX is the first and only mount I've ever purchased. Given the pricetag and advertisements, I knew I wasn't getting the top of the line, but figured I would at least get something that worked with no major issues out of the box.


I think my rationalizing was that I had such good success with my original CGEM that I assumed maybe Celestron finally got it right, and the DX was enhancement on an already good thing.

However, like Madratter suggested - mine was acting more like my CG-5 did out of the box. If that's what I could expect, I'd rather lift a CG-5 any day over this DX - it's a cumbersome mount for sure. For four times the cost though, it should do significantly more, as advertised. Lots of great results out there from people using the DX, but I have to wonder about the others who aren't having as much luck. I suspect this will be a fantastic mount now that it's cleaned up and properly assembled. Just wish it arrived that way out of the box.

#17 DaemonGPF

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Posted 09 July 2013 - 01:48 PM

Great article and thank you for sharing. As someone who is looking to get serious about AP, I find this sort of material extremely helpful. And I don't mind rolling up my sleeves to get things in proper order.


Thanks. I'm glad to hear this was helpful. Sometimes a little elbow grease can go a long way as I've found with all of my various mounts. Further than the stock grease Celestron uses..
:lol:

#18 CounterWeight

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Posted 09 July 2013 - 02:44 PM

I too really like the ASPA and all other hand controller firmware and menu structure! Of all I've tried it is my favorite. Something like that on my mach1 would be best of all worlds. Tradeoffs everywhere. In a way it's like with the old days of cars, some were more a 'mechanics car' that were fantastic if you were good at timing and synchronizers, new how to play with a suspension, and could play with the valves and manifolds and block, etc. I'm really interested in this mount - but not the issues. If that is what Ed does to these to make them work better I think that is coin well spent!

Looking forward to some 'after the tune-up' images and happiness!

#19 WesC

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Posted 09 July 2013 - 05:46 PM

Wow, that is impressive! I have a CGEM and haven't tried AP yet (scared to frankly) but I have noticed a few times that the mount seems to struggle and makes odd sounds. Very good balancing helps a lot, but I can't help wonder what it looks like in there and it I should ship it to DSP for Hypertuning. I just have a fundamental issue with spending more money to fix something that should work right to begin with. In my case it may be better to just sell it and buy a Mach 1, used AP900 or if I can swing it, an AP1100.

#20 Madratter

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Posted 09 July 2013 - 07:02 PM

haven't tried AP yet (scared to frankly)


Do you want to be enabled or should we tell you the truth about what this hobby costs?

Actually, it sounds like you have a pretty good idea. :p

#21 DaemonGPF

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Posted 09 July 2013 - 07:21 PM

Maybe he's the smart one.
:smirk: :lol:

#22 shrevestan

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Posted 09 July 2013 - 07:40 PM

Nice NES collection too, btw.

#23 Madratter

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Posted 09 July 2013 - 07:40 PM

Let's just say that with I'm running about 110$ a picture with expense this year/# of pictures taken this year. Ouch!

:foreheadslap: :help: :tonofbricks:

Would I do it over again. Yup! :crazy:

#24 DaemonGPF

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Posted 09 July 2013 - 07:45 PM

Nice NES collection too, btw.


Thanks! I collect game consoles. I have everything in working order, back to the Atari 2600 with the exception of the Intellivision, and up to everything current. Could probably sell that collection and swing a nice AP mount. Hmm...
:idea:

#25 shrevestan

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Posted 09 July 2013 - 08:01 PM

There should be a way to combine the hobbies. Enter in the Konami code on the hand controller and get 30 extra subs.






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