G11 owners

Phil · #1 17-05-2007, 07:54 AM

Hi has anyone had problems with the altuide on there G11 as i went out last night into the obsevatory and shot a 20min exp. to find that there was feild rotation in the photo. This was not good as i just done a drift alinement the other night and everything was fine. I then took the camera of and checked the alinement doing drift again. I found that the altuide had moved. Has anyone had this problem.
Thanks for reading any suggestion.
Phil

gbeal · #2 17-05-2007, 08:26 AM

It is a while since I had a G11, and when I did it was one of the earlier ones that had only the single altitude bolt. This "could" slip, and possibly that sounds what you have had happen.
The later units had two "bolts" one central pivot bolt, the other a locking bolt off to one side. If you are not worried about the cosmetics, get one installed (assuming you are currently one bolt, not two).
Otherwise, a BIG ugly socket, and a new stainless high tensile bolt/nut.
Gary

Phil · #3 17-05-2007, 08:35 AM

Mine has 2 bolts but still sliped maybe was the wieght i had on it.

JohnG (John) · #4 17-05-2007, 08:46 AM

In a word, No.

I have had a GM-8 for close to 8 years with no problems and a G-11 close to 4 years and again no problem.

Both my mounts have the dual bolt altitude adjustment system. Are both sides of your bolts tight ?

Did you perhaps bump the mount and move it slightly ?

Balance is critical with the GM-8 and G-11.

Cheers

John G

[1ponders] (Paul) · #5 17-05-2007, 10:13 AM

That is a big no for either 8 or 11. Are you pier mounted or tripod mounted Phil?

leon · #6 17-05-2007, 10:25 AM

Although I have only had my G11 for about 4 months, I have to say the only time i had that problem was when i had adjusted the mount and had forgot to tighten both the locking nuts.

Other than that it has performed flawlessly.

Leon

Robby · #7 18-05-2007, 07:44 PM

Yes, I have a similar problem with an older G-11 (single bolt). Funny that Gary!

There is a bit of flex when load is added or removed, and this is what I guess causes the slip.
Not too much you can really do, except keep the weight as balanced as possible. Mine doesn't slip too much, but I'm hoping once it's permanetly installed the problem will go away completely.
What camera are you using? You might be better of taking a series of shorter exposures and correcting for any field rotatation during post processing.
Cheers

Phil · #8 18-05-2007, 07:52 PM

I am useing the STL-11000M. I have realined everything
and have the camera cooling now. See how i go.
Phil

rsbfoto · #9 18-05-2007, 11:08 PM

Quote:

Originally Posted by Robby

Yes, I have a similar problem with an older G-11 (single bolt). Funny that Gary!

There is a bit of flex when load is added or removed, and this is what I guess causes the slip.
Not too much you can really do, except keep the weight as balanced as possible. Mine doesn't slip too much, but I'm hoping once it's permanetly installed the problem will go away completely.
What camera are you using? You might be better of taking a series of shorter exposures and correcting for any field rotatation during post processing.
Cheers

Hi Robby,

There is a simple fix for your problem. Look at this image

http://www.rainerehlert.com/astro/CelestronG12.jpg

http://www.rainerehlert.com/astro/CelestronG11.jpg

That is a 11 year old G11 made for Celestron by Losmandy.

I made 2 plates, tapped a hole into the upper moving RA part and voila I got a better fix then as the newer G11 mounts.

saludos Rainer