Very strange guiding problem....

[stan26]

Hi Folks, I set my gear (as per sig) to image M51 last night but ran into a very strange guiding problem that after a few hours I was still not able to cure. Before I go any further I will ask the question to the more experienced imaging crowd on here - can you successfully image straight up right over head i.e where M51 would have been around 11:00pm last night...? this could be my problem I have never imaged at this ridiculous angle before!

The problem is with DEC, after a successful calibration using PHD guide software the guiding will commence and it will be fine for approx 2mins then the star will rapidly shoot south for no apparent reason sometimes going completely off the screen! I purposely miss aligned my mount so that the star drift would be north and and set PHD to guide north only. The same happend, perfect guiding for approx 2mins then the star shoots off to the edge of the screen but this time north. I thought it might be the DEC motor or software having a funny moment but I put my finger on the DEC motor during the guiding to feel the pulsing and nothing feels out of beat when it goes hay wire...? Could this be caused by a sticky DEC axis...?

Thanks

Stan

[sgazer]

i had a similar problem, but with Guide Dog which was never resolved. Sometimes, the DEC direction was reversed (not all the time). So I'd start guiding, looked fine (probably as no DEC corrections were required), then once DEC kicked in it would go off the screen. I would tick the reverse DEC box and it would be fine. Never new why I had to do this only sometimes, I could restart Guide Dog and it would have changed! Might be your problem, might not.

[stan26]

Thanks sgazer, Not sure if PHD has reveres DEC option, il check later.

To me its almost like the DEC axis is sticking and somewhere between motor and wormgear there is a build up of pressure untill it finally lets go and flys off the scale.....

Hmm