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SouthernSky
18-02-2019, 01:16 AM
Hi! I have just bought a Celestron 9.25 Edge and a Skywatcher AZ/EQ 6. I find mounting the scope in EQ mode fairly easy but considerably more difficult in AZ mode. The scope's dovetail is wide and involves expanding the clamp
pretty much the limit to insert it. Just wondering if anyone has any tips or tricks to get the scope on the mount safely (have balanced everything). Also, when in AZ mode should the counter balance weights go on first?

Thanks.
SouthernSky

The_bluester
18-02-2019, 05:54 PM
It is just a matter of care getting the scope on, just make sure you have the knobs for the dovetail clamp to the top.

And yes, the counterwiights go on first. A good way to see how much weight is required is to set it up in EQ mode and balance both axis in that mode to work out where it should all be. It does not seem as critical on the az axis in alt-az but it has to be nicer on the bearings if it is well balanced. The alt axis is easy enough to check in that mode.

Wavytone
18-02-2019, 07:41 PM
Yes there is a way, and I'll see if I can find a video demonstration (have seen one).

1. Assemble mount with dec axis and fit the counterweights in the right position. Set the dec axis so the dovetail clamp is ready to take the OTA pointing vertically down, and clamp.

2. Place an observing chair or similar at max height under the dovetail clamp.

3. Lift the OTA and place it on the chair with the corrector pointing down - assuming the cover can take the weight of the OTA without buckling. If you are worried the cover will buckle then point the scope up but the chair has to be higher.

4. Manouvre the dovetail into the clamp, and do it up, letting the chair take the weight of the OTA (not your back).

This assumes you have a reasonably good observing chair you trust to take the weight without collapsing or falling over.

Second method - no chair. Even if you are tall and reasonably strong the worry is dropping the OTA. Head to Bunnings and buy a 2m strip of Velcro that is double sided, ie one side of it sticks to the back of the strip for a few $. With the OTA in the boot of your car, pass this around the OTA and make a loop over one shoulder, like you would hold a broken arm in a sling, let this take most of the weight. Once on the mount rip the Velcro off. A strong shoulder strap off a bag will do the same job, I must have a half a dozen lying around unused.

The_bluester
18-02-2019, 08:22 PM
Interesting methods, my OTA has the narrow dovetail on it but I never found handling it to be much of a problem. I just put it on with the tube horizontal, get the clamp just open far enough to take the dovetail and rock it in, then hold the OTA in place with one hand and arm while doing up the clamp.


I am using it in EQ mode now so it is a while since I have done it and I can't recall exactly how I arranged it all, it got to be automatic/muscle memory for me.

Wavytone
18-02-2019, 10:19 PM
Here... assembly is the reverse sequence (he’s using a C14). https://m.youtube.com/watch?v=IwVg1M6bURI

SouthernSky
19-02-2019, 09:29 AM
Thank you everyone for your tips, advice and YouTube demos. Very much appreciated.

casstony
19-02-2019, 09:42 AM
I find alt/az mounting much easier than equatorial - just hold the tube against my chest with one arm while tightening the saddle bolts with my other hand.

Wavytone
19-02-2019, 10:10 AM
The other thing is getting the setup right is so much easier in AZ mode. On Sunday I set up in EQ mode for the first time in ages and totally flapped up during the alignment routine - had the polar axis waaay off the SCP, and forgot to tighten the RA clutch ! Had to fix and redo three times LOL...

The_bluester
19-02-2019, 11:11 AM
The only extra care I found required in alt-az mode is leveling the base is a lot more critical than in Eq mode.

Wavytone
19-02-2019, 12:05 PM
Funny you say that. For some time based on the errors seen in GOTOs I have suspected the SynScan firmware assumes it is dead level, ie makes no correction for the tripod being tilted.

The_bluester
19-02-2019, 01:18 PM
I think that is the case. I found that the more carefully the tripod head is leveled before putting the mount head on the better the performance on the night.