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Guide scope help


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I recently picked up a QHY5-II-M for autoguiding for a good price for when I start my astrophotography. I am still gathering all necessary pieces for this. Does the guide scope for the QHY5-II-M it is attached to need to be "synced" to my scope? Just using logic, I would think that it could create error if the guide scope/camera is not on the same page. I know, very scientific terminology.... The telescope I am going to be using for imaging is a Celestron C8N F/5 on AVX. I see QHY sells a Mini Guide Scope but am unsure if this is a good match for my scope. Any advice, or recommendations (preferably ones that don't break the bank) for a guide scope? TYIA.

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As long as the guide scope and imaging scope roughly point in the same direction, you should be ok. Roughly being a few degrees or less off. I have my sw st80 guidescope bolted on top of the main scope, and haven't even checked how much off it is.

If you use a finder scope as guide scope, you should be more concerned about any movement relative to the main scope (= differential flexure), which can ruin guiding. Make sure that whatever guide scope you will use, it is securely fastened to the main scope.

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The rule that I followed for guiding is that the F ratio of the guide scope is equal or quicker than the main scope.  In my case, I have a Meade LX-90 (f/10) and use an ST-80 as the guide scope (f/5)   As the guide scope is quicker, that means it will show more "seeing" related issues.  Which means that if I get the autoguiding setup and tuned so that I'm not "chasing the seeing" the main scope will take a lovely stable image.

Apart from the F ratio, just make sure that you mount whatever guide scope so that it's pointing in roughly the same direction as the main scope. Make sure that it's secure and does not move as this will throw off the guide software.

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