#82245

I have a G11G, and just got a 130mm Stellarvue refractor to image with.? ?I've got an 11lb and 20lb counterweight currently, trying to figure out if I should use more.? The scope weighs I think 21lbs with rings, and adding the camera, flattner etc I expect to be about 25-28lbs.? ?Seems to weigh less than my fully loaded C11, but the 30ish lbs of counterweight didn't seem quite enough for that scope.? The weight is much closer in with this refractor.? I can get it to balance, but won't be able to test under the stars for tracking for quite a while based on forecast and travel plans.??

I had posted here before an a number of folks were using refractors in this class/weight range.? What did you find was the 'right' amount of counterweight??

Brian

#82246

130mm refractor with focuser, EFW, flattener and cooled camera = 32.4lbs. I use a 20 and an 11 - 20 is up high on the shaft (less than 2" from top) and 11 is around mid way on the CW shaft.

Calcultae the distances also from below links but final manual adjustments were needed for me.

Good luck,
Ken

#82247

AT130 at about 27.5 lbs. One 21 lb counterweight.

#82255

开云体育

A lot high up.. I used all three with my SV 130..

Derek

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From: [email protected] [mailto:[email protected]] On Behalf Of BBasiaga via groups.io
Sent: Wednesday, April 10, 2024 8:32 AM
To: [email protected]
Subject: [Losmandy_users_io] How much counterweight are you using with your 130mm refractor?

?

I have a G11G, and just got a 130mm Stellarvue refractor to image with.? ?I've got an 11lb and 20lb counterweight currently, trying to figure out if I should use more.? The scope weighs I think 21lbs with rings, and adding the camera, flattner etc I expect to be about 25-28lbs.? ?Seems to weigh less than my fully loaded C11, but the 30ish lbs of counterweight didn't seem quite enough for that scope.? The weight is much closer in with this refractor.? I can get it to balance, but won't be able to test under the stars for tracking for quite a while based on forecast and travel plans.??

I had posted here before an a number of folks were using refractors in this class/weight range.? What did you find was the 'right' amount of counterweight??

Brian

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#82260

All 3 of which size??

Sounds like i may be in the ballpark with the 20 and 11 I have....just need a chance to give it a try....

Brian

#82261

Last time I put a C11 with a 3" DT bar on a scale it was over 30. IIRC 32+. Surprisingly, the G9.25 weighed almost 28.

#82263

开云体育

20.. 11.. and 7# Losmandy weights.. Yes, the 20 and the 11 will work, but higher up / closer to the scope is “better”..

Derek

?

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From: [email protected] [mailto:[email protected]] On Behalf Of BBasiaga via groups.io
Sent: Thursday, April 11, 2024 5:30 AM
To: [email protected]
Subject: Re: [Losmandy_users_io] How much counterweight are you using with your 130mm refractor?

?

All 3 of which size??

Sounds like i may be in the ballpark with the 20 and 11 I have....just need a chance to give it a try....

Brian

?

Virus-free.

#82271

On Wed, Apr 10, 2024 at 08:32 AM, BBasiaga wrote:

I have a G11G, and just got a 130mm Stellarvue refractor to image with.? ?I've got an 11lb and 20lb counterweight currently, trying to figure out if I should use more.? The scope weighs I think 21lbs with rings, and adding the camera, flattner etc I expect to be about 25-28lbs.? ?Seems to weigh less than my fully loaded C11, but the 30ish lbs of counterweight didn't seem quite enough for that scope.? The weight is much closer in with this refractor.? I can get it to balance, but won't be able to test under the stars for tracking for quite a while based on forecast and travel plans.??

I had posted here before an a number of folks were using refractors in this class/weight range.? What did you find was the 'right' amount of counterweight??

Brian

Brian,

The best thing to do is to set it up and try it. The counterweights would ideally be located about the same distance from the axis as the center of mass of the scope over the DEC axis. For a refractor on a Losmandy D dovetail this is someplace around mid-shaft of the standard G11/GM8 CW shaft. If your counterweights are not in the middle then just change them up, I usually use a 21# and an 11# for the bespoke Parallax/AT130mm f/6 SDT imaging rig. I place the 21# in the middle and move the 11# in and out depending on what other bits are hung on the tube.?

When I have the 130mm imaging rig and Takahashi FC-100DL for visual with a ADM alignment platform in a side-by-side setup it is pretty heavy and I use 2 x 21# with a 7# on the end for balance.? ? ? ??
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Chip Louie Chief Daydreamer Imagination Hardware?

? ?Astrospheric Weather Forecast - South Pasadena, CA?