brendan I think you are correct its my guiding, I have heard that dreaded donk heaps of times. Although the photos I attached of the stars It didnt donk at all it just kept the star pretty good centre of guide crosshair in PHD.
But they are only 1 minute exposures
I could here the correcting adjustments it was doing to mount. One thing I usually set it for 1 second corrections maybe this is wrong maybe it should be longer?
An other thing I forgot to mention is I always start up PEC playback in celstron hand controller before I start guiding with PHD, maybe this has something to do with it?
Quote:
Originally Posted by bmitchell82
like i said something is totally amiss, if your getting that much drift in 1 minute your not anywhere close to polar alignment. moving the weights around will not affect if your motors run fast or slow if they do then you either have some massive weight on them or they arn't upto the task of astro photography! it will affect guiding though. but in any case your PHD will be going off its face and donking like a mad man (anybody who has heard the dreded donk will know what im talking about).
What angle is your wedge plate at? it should be at 66 deg.
if your polar alignment is right then your guiding has some problems aka wrong settings. Run a quick test shot without guiding and see if the problem still occurs.
When im guiding with PHD i bias the weight to the side im working with because i am over the recomended weight limit of the eq6 this just helps with a bit of back lash, if i do put the weight to far one way they guiding in Dec stuffs around but easily fixed.
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