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Old 19-11-2015, 11:08 PM
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lazjen (Chris)
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Join Date: Dec 2012
Location: Flaxton, Qld
Posts: 2,064
Quote:
Originally Posted by Ryderscope View Post
Hi Chris,

Some more advice on balancing. May not help but if your busy trying things why not?

I find with my EQ8 that it is quite sensitive to balance and if I don't get it right I will see a reduced guiding performance. Not to the extent that you are seeing but worth looking at all the same. This may not be relevant to the G11 but worth checking.

As well as balancing in RA and DEC, I find with the EQ8 that it is important to also make sure that the weight is evenly distributed laterally across the top of the mount where the OTA sits. In other words if you are standing behind the mount looking at the OTA pointing towards the pole, the weight should be distributed evenly on each side of the OTA.

It may be easy to assume that this would always be the case but in many cases the finder scope will not be in the centre of the OTA but is off to one side. If this is the case and depending on the mount, the centre of gravity and balance point will shift as the mount moves in RA.

In my case with the EQ8, if I move the mount in RA and I haven't got this third balance point correct then it may seem to be balanced when checking in the 'classic' way with the counterweight bar horizontal. If I then move the mount manually in RA however I will find that there are points where the scope/counterweight will not stay in position and will drift to the centre of gravity point. This is further complicated with the EQ8 due to the position of the motors so may or may not be an issue in your setup.

I would recommend testing your set up by loosing the RA clutch and manually pushing the counterweight bar around in small increments. Make sure that each time you let go of the counterweight bar that the OTA/counterweight bar stops at the point you let it go. If it starts to move of its own accord when you let it go (even after you have checked the RA/DEC balance) then it might be worth checking the lateral balance as indicated above.

When I have had issues with this in my current set up I have simply rotated the OTA so that the lateral balance is correct. I note that you may be using a GSO RC10 so I am unsure as to how you may do this.

Sorry for long post but it might just be worth a shot.
I'll check this, but I think it won't apply to me. I don't bother attaching the finder scope most of the time, since I never really use it.

The set up is almost the same as what I've used in the past. I've taken out the focal reducer and put in a spacer before the focuser. Other than that, I can't think of any other configuration changes and those should have no real impact.

*********************

For those that have made suggestions:

Tomorrow night I'll try some adjustments again and test. I'll collect some measurements and post the details/pics. If there's any specific test and result pic you'd like to see, please reply and I'll try to get it.

I'm currently using PHD2 for testing.
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