When you get it so wrong, why does it work out right?

[Tim]

Recently I bought a big fat ten inch Skywatcher imaging Newt. Got it all mounted up in my little obsy, and got the first results in. The tracking via the autoguider was reasonable, but not as good as what I am used to, but its a lot bigger scope wise.

Thought nothing of it, until this week I noticed that the tracking was really good, so it must have settled down I thought.

But then I came to manually swing the scope around on the mount to collimate it, and horror of horrors it swung wildly and was completely unbalanced. Apparently one night I had switched to my C9.25 and removed the third counterweight, and not put it back on for the 10", so it was really heavy scope side.

I put the missing weight on, and now the tracking is back to just reasonable........

I dare not leave the weight off, even though the guiding results were better!

Have any other members found stuff out like this???

Cheers

Tim

[cathalferris]

Balance it just barely scope heavy for when the tube is east of the mount. For the other side of the meridian, have a magnet and a small weight (or a ankle-weight for running). Should ensure that the motors are always slightly climbing uphill - should reduce a little bit of the problem that you are seeing.

[Tim]

Thanks

I generally only image with the scope west side, and keep the weights side heaviest. I keep some speaker magnets stuck to the pier for 'just in case'!

Cheers

Tim