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GPDX / EM10

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#1 Emanuele

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Posted 12 December 2010 - 11:38 AM

Hi all.

Just wondering if a GPDX or EM10 could carry an FSQ85 + FLI ML8300 + CFW2-7 + accessories.
I think it is almost 30lbs of payload.

Would one of those two mounts be enough for AP with the FSQ?

Thank you,
E.

#2 jsiska

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Posted 12 December 2010 - 08:44 PM

In my 2003 Vixen catalog the maximum loading weight (OTA + camera equipment) for the GP-DX is 10kg = 22.046 pounds. The required counter weights for operating the GP-DX was not counted as a factor in the max loading weight.

Newer catalogs may have stated a much higher maximum loading weight; however, as I understand it this higher max loading weight includes the counterweights.

From:

http://web.archive.o...adjust_backlash

Notice that for unguided astrophotography Ron Wodaski author of THE NEW CCD ASTRONOMY was able to get 90 to 120 seconds without star trails to 6 arcseconds without PEC. To accomplish that Ron had a 7.711kg = 17 pound load on the mount.

Jim
----------------------
GPDX-C102F with Moonlite Motorized focuser + Skysensor 2000PC version 2.06 with version 2.10 chip.
Meade 880, 8” f/6 RG Newtonian.
Meade 10" f/4.5 Starfinder dob.
Tasco 7TE, 60mm, f = 910mm,
1962 60mm, f/11.7 Tasco 9TE with custom visual back & remounted on a GEM.

#3 Gary.McK

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Posted 12 December 2010 - 09:34 PM


I have a Vixen GPD2, which tracks beautifully, but I do not think that it would carry the weight you want to. It is rated at 10kg (about 22Lbs). Mine is currently carrying 11.5 kg (about 25 Lbs) I think this is too much for imaging and I intend to move to a lower weight by re building my OTA in carbon fibre. I would think that for rock solid imaging about 8 or so kg (17-18 LBS) would be nice. Mind you my rms tracking errors with the above heavy system are limited by my local seeing. I get better than .2 pixels rms with a 200mm guidescope and qhy5 camera. I just feel like the mount would be doing things easier with a lower weight.....
fwiw
Gary

#4 bardo

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Posted 12 December 2010 - 10:15 PM

my GPDX could handle about 20lbs imaging at 1300mm just fine.

#5 Panotaker

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Posted 12 December 2010 - 11:02 PM

I have imaged with my GPDX carrying a AP-130f/6 on a windless night with no problem. A slight breeze would have made it impossible. I can image with it carrying my TV85 with no problems. I use a converted finder as my guide scope. I would think it should handle a 4" refractor since that is what Wodasky used. I believe he used an AP Traveler.

#6 Emanuele

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Posted 13 December 2010 - 06:18 AM

Thank you guys for the feedback.
Judging from your replies, I think the GP-DX and Em10 are not going to be able to hold the FSQ and CCD. Ot least not when a slight breeze is present.
The mount market needs a slightly higher capacity mount, comparable to those two...

E.

#7 Rat8bug

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Posted 26 December 2010 - 12:44 AM

The GP-DX load limit of 22 pounds has always been conservative. This Vixen will easily handle about 28 lbs, using proper counterweights and tripod imo.

http://www.barrie-ta.../wotriplet.html

Ciao...Barry

#8 Gianluca67

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Posted 04 January 2011 - 05:09 PM

I agree. I use the GP DX for CCD imaging and can get unguided single exposures up to 2 min at 800 mm fl with 28.5 lbs (13 kgs.) on it as well as 12 Kgs. of counteweights. No issue at all. About wind I have found that if it is more than breeze the GP DX does not work optimally regardless of the load.

Ciao

Gianluca

#9 SPACEMAN

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Posted 11 March 2011 - 05:31 AM

thanks everybody for this topic, i also have an Vixen GP DX,
and i have a M100B from lichtenknecker Optics. For the M100B The heavy weight 35cm(14") tube will go on that mount.
For imaging with the 20cm telescope, i want to buy paralax rings. But they are heavy: 7lbs, Total weight wil be around 12kg also, so if read this, i will be good with mine old green version gp dx :)






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