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Will Hypertuning a Celestron DX or Cgem help improve balancing?

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#1 johnd39818

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Posted 28 July 2014 - 10:09 PM

Id like to hear peoples experiences after hyper tuning a Celestron DX or CGEM mount. I have had a mixed bag with mine in astrophotography all to do with balancing. I have some striction in both axis so its hard to tell if I am truly balanced. When its on its on and I can do 15 minute + guided subs when its off no so well. I was wanting to hear others experience' after having yours hyper tuned and the difference it make or didn't make.

#2 orlyandico

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Posted 28 July 2014 - 11:57 PM

Yes.

My CGEM (non DX) had a fairly tight RA axis even with the clutches loose, and this made balancing really difficult.

Polishing the RA and DEC worm wheel surfaces significantly improved the rotation of both axes when declutched, which made balancing much easier.

BTW my "hypertune" was limited to polishing the RA and DEC worm wheel surfaces (inside and out), replacing the RA worm with an Aeroquest, and replacing the RA worm bearings with SKF 608ZZ bearings.

Each of them provided a minor improvement, but my CGEM had a lot of 8/3 (more than the worm fundamental) which seriously limited the guided performance. At the end of the day, all the hypertuning in the world won't turn a pig's ear into a silk purse. That said, if you can get 15-minute subs out of your DX, then you almost certainly got a better sample than I did.

#3 johnd39818

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Posted 29 July 2014 - 01:20 AM

So you also replaced the RA and Dec worms?

#4 orlyandico

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Posted 29 July 2014 - 01:30 AM

Just the RA worm. The stock worm had about 30" of PE, the Aeroquest had 16" so in theory a major improvement.

However my CGEM had about 25" of 8/3 (!!!!) so with the stock worm, the total PE was about 42" (the 8/3 is not in phase with the fundamental, so they are not purely additive). With the Aeroquest worm, the total PE got reduced to... about 35" or so. Not so great.

Most CGEM's these days supposedly have under 8" of 8/3. So replacing the RA worm could drop the PE from 30" range to perhaps 20" range.

Like I said, it's an incremental improvement, and all the increments add up, but you still will not get G11 or AP performance after all your tweaks and hypertuning (I ended up with an AP - and it has under 3" p-p native PE, and under 1" after PEM training).

At the end of the day, what matters is the RMS guiding performance. I could never get much below 2" RMS with my CGEM. That limits how long you can go, and how fine a pixel scale you can get.

#5 dragonslayer1

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Posted 29 July 2014 - 09:04 AM

Check out Ed Thomas of Deep Sky, he has all the info, kits, and does hyper tuning if need him to.. Has stellar reputation, sometimes is on here but haven't seen him for a bit...
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