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GM8 for a 25lb 6" F8 refractor?

Started by Bill in Ballard, 03/03/2006 03:33PM
Posted 03/03/2006 03:33PM Opening Post
I have have a 6" F8 refractor and have been using an old Mead6 826 mount on a home made pier. The Meade is plenty solid and it tracks well with the scope. I would like to upgrade & have been looking at the Losmandy GM8.
I am strictly a visual observer, and was wondering if the GM8 would have the capacity to handle the 6" scope? The OTA is about 20lbs, and is nearly 25 lbs. with a 35mm panoptic, diagonal, and chromacor.

My primarty interest in the GM8 is the setting RA circle design which (if I understand correctly) does not have to be reset moving from object to object.
Posted 03/03/2006 04:11PM #1
Bill Barrett said:

I have have a 6" F8 refractor and have been using an old Mead6 826 mount on a home made pier. The Meade is plenty solid and it tracks well with the scope. I would like to upgrade & have been looking at the Losmandy GM8.
I am strictly a visual observer, and was wondering if the GM8 would have the capacity to handle the 6" scope? The OTA is about 20lbs, and is nearly 25 lbs. with a 35mm panoptic, diagonal, and chromacor.

My primarty interest in the GM8 is the setting RA circle design which (if I understand correctly) does not have to be reset moving from object to object.

I use a GM8 with a G11 tripod, and it handles my TMB 115 CNC for imaging - the weight is roughly the same as your setup - but my tube is probably easier to swing because it's shorter, and will catch less wind.

I have the Gemini system, mostly because the cost difference between Gemini and digital setting circles wasn't that much when buying a new mount.

But IIRC the RA setting circle that comes with the mount won't be accurate if you slew with the motors, and they'll lose some accuracy if you use the RA motor to center objects in the field.
Posted 03/03/2006 08:47PM #2
I wouldn't put a 6" f/8 on a GM-8 - dampening times would be horrible.

I agree with Ed, an Atlas EQ-G would be a better choice. It supports my Meade 102ed and Vixen ED80sf plus imaging equipment and doesn't even cough.

-Jake

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jjacobso's attachment for post 101429
Posted 03/04/2006 04:13AM #3
As always you have all been very helpful.
It looks like I would indeed be better off with an Atlas or a G11. thank you, Bill
Posted 03/04/2006 10:55AM #4
I threw my AR-6 on it for giggles and it works fine. Gemini is right on - although I run at 18v. I have the 12" pier extension so hight is not a problem. I also have the "old" non adjustable "round" legs tripod - which I think is far more stable then the current "square" adjustable one.