Erratic Slewing... Weight Issues?

[cshahar]

Hi Everyone:

I have a CG5 mount. I actually don't use the hand paddle anymore. I am hooked up to my laptop with NexRemote. I am doing solar imaging. The problem I am having is that when I try to slew in a certain direction the mount slews at a much quicker rate and I lose the sun. In the other three directions it will slew at an appropriate rate. I am just wondering whether I am not being sufficiently careful with balancing the scope. The imaging accessories are quite weighty and maybe I should balance test more at the end of the process rather than at the beginning? Are there any other reasons that might be responsible for this erratic slewing? The slewing is also occasionally not responsive taking a few seconds before it moves.

Thanks!

-Charles

[MarsG76]

Sounds like either its not balanced or your equipment is too heavy for the CG5...

[cshahar]

Well, its a 4-inch refractor (which I should have mentioned), well within the CG5 capability.

[Tinker1947]

Have a look at the power supply, is it stable.....

[philj]

Possibly balance issues. 1 direction you are driving against the weight therefore backlash is taken up the other direction the mount has to take up backlash then due to it being biased in that direction it drives easier. Thus nexremote or handbox control will make no difference it will happen with either. Easiest way to prove it is to try it with the handbox in the same set up.

However its always good practice to balance with a slight bias one way, this will avoid strsin on motors/gears etc

[cshahar]

Thanks. Can you explain why bias it one way? And how do you know which way?

[malc-c]

Sounds like a balance issue.  What other scopes, cameras etc us attached to the mount.  Whilst you can balance the scope across the RA axis, and then balance the scope across the dec, it also need to be ballanced evenly along the focal axis, eg with the scope in the traditional home position, standing in front of the scope, is the finder equally opposite the focuser / camera...

Have a look at Dion's Tutorial 

And to explain the bias

[cshahar]

These are exceptionally useful videos. Thank you for taking the time out to share them!!

-Charles

[malc-c]

Not a problem.  Dion hasn't posted a video for over a year, but his channel has a lot of information on setting up and using a scope and is well worth spending a few hours checking them out