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CGEM saddle height

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#1 nobake

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Posted 08 March 2011 - 09:23 AM

Hi,

I’ve searched for the height of the saddle on a CGEM mount but can’t seem to find it.

I would like to put an 8” f/6 newt on one but don’t want to have the eyepiece too high in the air. I’m tall enough it won’t matter to me but I would rather sit and if anyone else views I’d prefer not to have them use a stool.

So if anyone has this information please let me know.

Thanks,
Matt

#2 nemo129

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Posted 08 March 2011 - 11:24 AM

Wouldn't how far the tripod legs were extended affect the height of the saddle? I think you might be looking for a minimum and a maximum height. I'd measure for you, but mine is packed away right now, as I have a G11 coming soon and needed to make room. Perhaps posting in the Yahoo CGEM users group may get you an answer if one is not forthcoming here.

#3 nobake

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Posted 08 March 2011 - 01:02 PM

Thanks Kirk,

I'll go search over there.

And yes, minimum height is what I'm after.

thanks,
matt

#4 Adam E

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Posted 08 March 2011 - 01:40 PM

With RA rotated so the head is perpendicular to the ground, the center of the saddle is 47 inches from the ground. With RA rotated so the head is parallel to the ground, the center of the saddle is about 40 inches from the ground.

Not sure how much this is going to tell you though, because a Newt on a GEM will have the actual eyepiece height all over the place depending on your tube rotation and where you're pointing.

#5 nobake

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Posted 08 March 2011 - 02:56 PM

Thanks, that's what I wanted to know.

I know the eyepiece will be all over, I just didn't want it super high. I had one mount which put the eyepiece too high for me.

thanks,
matt

#6 DL Sharp

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Posted 08 March 2011 - 03:09 PM

I use an 8" f/6 newt on my CGEM, and found that the eyepiece height was often too high for me. I found a very good guide written by Peter Bruce on how to reduce the height of the CG-5 tripod (The CGEM tripod is virtually identical to the CG-5)

http://www.nexstarsi...podModBruce.htm

Using this guide, I cut 11 inches off the height of my CGEM's tripod, and turned the height adjustment knobs inwards, so they're not as likely to get snagged on anything. Now the eyepiece for my scope is always in a comfortable range for my adjustable observing chair, and it really feels a lot more sturdy than before. The only difference I noticed between this guide and my CGEM's tripod was the lack of epoxy in the main castings, and four allen set screws in the castings, not two.

#7 nobake

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Posted 09 March 2011 - 02:28 AM

thanks for the link David, it is very helpful to get photos.

Do you ever feel that your setup is at all unstable due to the smaller footprint of the tripod?

thanks,
matt

#8 DL Sharp

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Posted 09 March 2011 - 09:28 AM

Do you ever feel that your setup is at all unstable due to the smaller footprint of the tripod?


I was a bit concerned about that at first, but it is quite stable with the tripod positioned with one leg north, and the counterweight over it in the home position. (I'm at around 40 deg north latitude).

In the PDF document, the author has his tripod positioned with two legs north - That seems to me to be less stable, but a CG-5/C10-N combo might balance differently than a CGEM/8"f/6...






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