1st Shake out on the C11/CG-5 Mount Combo... Jun 13, 2013 15:55:34 GMT -6
Post by Chicago Astronomer Joe on Jun 13, 2013 15:55:34 GMT -6
First Raw Test of the C11 Riding on top of the New CG-5 Go-To Mount
13 June 2013
13 June 2013
The C11 Beast has proven to be a great scope, delivering views of the cosmos to thousands of fans over the years. I especially enjoy my solo one-on-one time with the scope - whenever I can get me some open sky locales....which is rare.
The mount it rides on, the Ci700, Celestron's answer to the Losmandy mount, does a wonderful job carrying all the weight I ask it to. C11, 102mm tracking scope, 9x50 finder scope 50mm aux. scope, laser guide, Extended dew shield etc... Tracks well, but is not a go-to and I spend more time star hopping to objects...and not all that quick. I have always desired a go-to mount for the C11, but a beefy mount, rated to carry bunches of weight is heavy on the pockets and out of the Chicago Astronomer's budget for now.
I have been having a blast with the new CG-5 mount that I got over the winter. Using the 10 lb C102 Refractor and the C5 SCT, I have captured great solar activity and the mount has shown me several DSOs, accurately and quickly. My intention though...was to see if I can load the heavy C11 on top of this mount. Many Astronomers before me are strongly adamant that this mount cannot carry such a tube...and at the very least, offer a very shaky platform - a useless combo. But, some others have paired this combo successfully without any problems, dismissing the doubters and prudes.
I like to dismiss the prudes too - and often, so I gave the C11/CG-5 combo a test shake out run this sunny and very windy day....with incredible success!
Leveling the tripod and snugging the accessory tray, I slip the OTA onto the ADM replacement Dual dovetail saddle, I tighten down the full length rail via two knobs...
I check for wobble and looseness, but nothing unusual.
I had placed two 12 lbs weights on the stock Counter Weight shaft, unsure if this would be enough. (I got me a 6" extension shaft that screws on the end of the stock one ...which really, did not know if I would need it. Counted on simple physics months ago for this day...and a good thing I did.) ...but it was apparent that I had run out of shaft.
Even with the two weights on the shaft, I was not getting proper balance, as it was still tube side bias heavy. Screwing in the extension shaft provided better balance, but not enough. Slipping a five pound weight, (which is not adapted to fit this shaft), cured this - making the counter weights at 29 pounds - the same weight as the OTA dry. But, I will need to attach the dual speed focuser, diagonal, 2" inch eyepieces, 9x50 finder scope...and the laser. Gonna need more weight... #drool#
In the Chicago Astronomer warehouse of goodies is another 12 lb weight that fits this shaft and bingo...
...we got perfect balance!
The bottom weight rests near the 9 ball and the others want to be about 3 inches apart up...
I totally loosen the clutches again and I push and nudge the scope around here and there...
..and the scope stays where I leave it, without tilting, leaning or spinning around in any axis and stable on both east and west sides of the mount.
I listen for some stress/binding while I manually move it about, but hear nothing - and the action is smooth. But I wonder how it will behave under power and motorized slewing. Will the motors complain or what? I return the mount back to it's home position and go through the set-up procedures on the Hand Controller for crude alignment. I hit the slew to the Sun command and it moves...
The motors purr away and make no different sounds than while carrying the much lighter 102mm refractor. I stay close to the OTA....just in case, but no need. Keeping the tripod legs short and maintaining a near perfect balance, the CG-5 slews the load without complaint. Even at an almost horizontal angle, the balance was good enough as to relieve the motors from fighting against the weight to a large degree. Using the hand controller, I nudge the OTA around, and the mount responds smartly and without slop.
How does it track?....'cause that's very important as well. I center the Sun's disk in a 26mm 2" eyepiece and leave it...
I return about five minutes later, keeping an eye, nose and ear on the whole assembly the whole time. We had the solar disk still well in the FOV and tracking well.
I'm impressed... and without proper polar-like alignment.
Now, of course the C11 should be riding on top something more beefier and substantial, but Celestron sold this duo as a package deal, meeting the minimal requirements for visual observation. Will it work for imaging?
Again, many Astronomer prudes nay say it is possible and call such an endeavour foolhardy. Perhaps, but this first shake out test performed without a hitch..and in very windy conditions. I did not observe any excessive shake that any other mount would dampen.
Whilst testing out this combo, a gentleman stopped by and asked what I was doing. Explaining that I'm Astro Joe and stuff, he remained with me for a bit and enjoyed observing the Sun throught the much better suited 102mm refractor...
He is a Dentist in the area and was pleased to discuss astronomy, equipment and related stuff like I tend to do. He has a house in Florida and has welcomed me to watch launches from the Cape and enjoy his palm tree filled property and wide open skies. Very generous and hope to take him up on his offer one day. He will attend a Chicago Astronomer session soon.
Back to the test....
More testing and shake-outs are in order, but I think that the combo will work nicely together if careful and diligent with the balance, level and take the time to make sure to use the anti-vibration pads. The 6" extension shaft is a necessity here and perhaps an additional tray near the bottom of the tripod is in order to help stiffen things up a bit. Some have constructed/bought one and seemed to help things.
But, I'm satisfied so far...