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Any tip for better tracking w/ fork mount for AP?

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#1 snowcrow


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Posted 09 January 2013 - 11:10 AM

I bought a CPC 1100 months before finding this site, so I'm stuck with it for now. I'd like to make the best of a bad situation by increasing the accuracy of tracking.

I did add a guidescope, counter weights, and trained the PEC. But I'm wonder if there is anything else I'm missing, just to tweak it a bit more. Thx.

#2 Mike Wiles

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Posted 09 January 2013 - 02:21 PM

Hi Bill,

Have you quantified how accurate the tracking is? Do you know how much periodic error there was before training? Do you know what the Peak to Peak periodic error is now with correction enabled? Those are the things I'd want to know next. You've taken some steps to improve your setup...so I'd start by assessing where you're at and figuring out how much improvement you've made.


#3 Footbag


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Posted 09 January 2013 - 03:00 PM

I started with a CPC-800. Personally, I think fork mounts are better at imaging then they are given credit for. I'd be surprised if your PE wasn't better then most similarly priced GEM's. And there is no reason why you cannot get great images from the setup.

My CPC-800 had a PE of 18 before PEC and 12 after.

#4 Peter in Reno

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Posted 09 January 2013 - 03:46 PM

CPC forks have unbalanced fork arms. The fork arm where the grip handle is pretty much empty inside. The other end of fork arm is loaded with gears, motor and other stuff. While CPC scope is mounted on the wedge and RA clutch is loose, does the scope wildly swing? If so, you may need to add some weights to the fork arm where the grip handle is. I think you might need about two pounds. I put 1.5 or 2 pounds ankle weight inside the fork arm in my old CPC0800.

You will most likely need counterweight for declination axis since you added a guide scope.


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