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Stabilizing the CG-5 with Al's oak legs.
At a recent star party, I had set up my CG-5/C-8 to track Mars for a public event. I had not used the Celestron CG-5 mount previously, because I had a Losmandy G-11 and dovetail plate to fit the C-8. It was unfathomably stable. You could rap the scope with a 2x4 and the vibration would dampen out in milliseconds. So I sold the Losmandy to acquire a big dob, figuring to replace it with a CG5 mount from Celestron. Let is put it kindly and say the CG5 is not a G-11. A touch of the focuser knob and Mars splits into two planets, maybe three, for 10 seconds or more. Tighten up all the bolts in the tripod, snug down all the allen screws on the mount, and maybe it will only split into two planets for 8 seconds. Focusing is virtually impossible, especially in a public star party with a wide age range of guests trying to get a clear view. A visit to google found that this is a generic issue with the CG5, and is widely attributed to flexure in the tripod system (or, the mount-earth interface, as I like to call it). What to do? Recommendations vary, from casting the aluminum tripod legs in concrete (makes portability an issue), filling them with sand, replacing them with a surveyor's tripod, and so on. Vixen uses wooden legs on the GP mount. That's a good recommendation in itself. Returning to google, I found http://www.alsastro.com, which seemed to specialize in replacement legs and leg kits for the CG-5 and the suicidally unstable LXD55 mount. With paypal, I ordered an oak leg kit for the CG-5 for $175 (includes shipping). The kit was shipped the same day, and arrived UPS ground four days later. Packaged in two boxes, the oak tripod members and leg clamps/aluminum leg stays, were undamaged. Finish was very good. If Al used wrinkle finish paint, and a redder stain, you would mistake it for a Vixen tripod. The clamps use galvanized thumb screws to lock each leg at its desired length. Al offers knobs as an option. I went to the hardware store. Assembly was simple. Two screws in each leg to hold the clamps. Insert thumbscrews. Remove aluminum tripod from CG5 mount to recycling bin. Install three bolts (provided) with wingnuts. Total installation time about 15 minutes (including time to look for misplaced tools). The legs are longer than the aluminum they replace, so taller observers will benefit (if the stand while observing). I'm 6'4" and the eyepiece is now right in front of my face. I set the tripod up and prepared for Mars rise the afternoon the legs arrived. C8, 7mm Nagler, 2X Barlow. No shakes. Focus to your hearts content. One Mars, not two or three. Finally I was able to appreciate what an excellent job I did collimating this scope. ;-) While some shaking is observed if the tripod is bumped, alignment is maintained and the vibration dampens out in 1-2 seconds. There is no vibration evident during focusing, manual dec slewing or any other normal activity at the eyepiece. I must say the kit for the CG5 is a well-made product at a very reasonable price. Finish is very good, appearance of the mount is improved. Performance is as stated (perhaps better). I would expect similar performance for the LXD55 kit. Regards, Etok __________________________________________________ ____________________ Posted Via Uncensored-News.Com - FAST UNLIMITED DOWNLOAD - http://www.uncensored-news.com The Worlds Uncensored News Source |
#2
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Stabilizing the CG-5 with Al's oak legs.
I agree. Great service, great product, great guy. Al rules!
Best regards, Bill "Etok" wrote in message ... At a recent star party, I had set up my CG-5/C-8 to track Mars for a public event. I had not used the Celestron CG-5 mount previously, because I had a Losmandy G-11 and dovetail plate to fit the C-8. It was unfathomably stable. You could rap the scope with a 2x4 and the vibration would dampen out in milliseconds. So I sold the Losmandy to acquire a big dob, figuring to replace it with a CG5 mount from Celestron. Let is put it kindly and say the CG5 is not a G-11. A touch of the focuser knob and Mars splits into two planets, maybe three, for 10 seconds or more. Tighten up all the bolts in the tripod, snug down all the allen screws on the mount, and maybe it will only split into two planets for 8 seconds. Focusing is virtually impossible, especially in a public star party with a wide age range of guests trying to get a clear view. A visit to google found that this is a generic issue with the CG5, and is widely attributed to flexure in the tripod system (or, the mount-earth interface, as I like to call it). What to do? Recommendations vary, from casting the aluminum tripod legs in concrete (makes portability an issue), filling them with sand, replacing them with a surveyor's tripod, and so on. Vixen uses wooden legs on the GP mount. That's a good recommendation in itself. Returning to google, I found http://www.alsastro.com, which seemed to specialize in replacement legs and leg kits for the CG-5 and the suicidally unstable LXD55 mount. With paypal, I ordered an oak leg kit for the CG-5 for $175 (includes shipping). The kit was shipped the same day, and arrived UPS ground four days later. Packaged in two boxes, the oak tripod members and leg clamps/aluminum leg stays, were undamaged. Finish was very good. If Al used wrinkle finish paint, and a redder stain, you would mistake it for a Vixen tripod. The clamps use galvanized thumb screws to lock each leg at its desired length. Al offers knobs as an option. I went to the hardware store. Assembly was simple. Two screws in each leg to hold the clamps. Insert thumbscrews. Remove aluminum tripod from CG5 mount to recycling bin. Install three bolts (provided) with wingnuts. Total installation time about 15 minutes (including time to look for misplaced tools). The legs are longer than the aluminum they replace, so taller observers will benefit (if the stand while observing). I'm 6'4" and the eyepiece is now right in front of my face. I set the tripod up and prepared for Mars rise the afternoon the legs arrived. C8, 7mm Nagler, 2X Barlow. No shakes. Focus to your hearts content. One Mars, not two or three. Finally I was able to appreciate what an excellent job I did collimating this scope. ;-) While some shaking is observed if the tripod is bumped, alignment is maintained and the vibration dampens out in 1-2 seconds. There is no vibration evident during focusing, manual dec slewing or any other normal activity at the eyepiece. I must say the kit for the CG5 is a well-made product at a very reasonable price. Finish is very good, appearance of the mount is improved. Performance is as stated (perhaps better). I would expect similar performance for the LXD55 kit. Regards, Etok __________________________________________________ ____________________ Posted Via Uncensored-News.Com - FAST UNLIMITED DOWNLOAD - http://www.uncensored-news.com The Worlds Uncensored News Source |
#3
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Stabilizing the CG-5 with Al's oak legs.
"Dan Wenz" wrote in message ... Etok wrote: At a recent star party, I had set up my CG-5/C-8 to track Mars for a public event. I had not used the Celestron CG-5 mount previously, because I had a Losmandy G-11 and dovetail plate to fit the C-8. It was unfathomably stable. You could rap the scope with a 2x4 and the vibration would dampen out in milliseconds. etc. Thanks for some useful information! Have you seen/tried the CG-5 mount with the "new" 2" tripod legs yet? The mount I mentioned is Part No. 91515. It features 3 element legs (2 upper, 1 lower) with a box cross-section. It is the "new" CG-5, in that it has ball bearings in RA--the tapered vs. the stepped RA housing. Here is the URL to the Celestron website mount page: http://www.celestron.com/access/eqm.htm The only CG-5 listed is the part number above. Regards, Etok __________________________________________________ ____________________ Posted Via Uncensored-News.Com - FAST UNLIMITED DOWNLOAD - http://www.uncensored-news.com The Worlds Uncensored News Source |
#4
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Stabilizing the CG-5 with Al's oak legs.
"Dan Wenz" wrote in message ... Thanks for some useful information! Have you seen/tried the CG-5 mount with the "new" 2" tripod legs yet? Further cruising the Celestron website and I saw the model you're referring to. It appears much more robust than the CG-5. I would go for this mount, personally. Regards and thanks, Etok __________________________________________________ ____________________ Posted Via Uncensored-News.Com - FAST UNLIMITED DOWNLOAD - http://www.uncensored-news.com The Worlds Uncensored News Source |
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