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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,

#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.



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.

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.....

#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...


#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.



#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.





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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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