Phd

[TrevorW]

For some reason tonight I could not get PHD to guide in Dec when pointing east but would guide perfectly when pointing south towards the crux, cause anyone

[Tandum (Robin)]

polar alignment?

Maxim worked to the east for me tonight until it got near azimeth. Then dec went up and ra went down on the graph?

PHD took over and just works?

[TrevorW]

Thanks Robin I thought it must be something simple as I normally have no problems with PHD, with me the Octans are blocked by my roofline and I'm yet to work out Alignmaster. Packed up by 12 was getting to frustrated and very cold 3 degree c, after jumping between the East and South trying to pick up targets worth imaging and having problems with PHD. To top it off my neighbour had a wood fire burning and the smoke obstructed anything to the NE.

[danielsun]

Trevor, Try rechecking your scope is Dec balanced. You might be a little too top or bottom heavy.

Cheers Daniel.

[Astrobserver99 (Rob)]

If I have dec guiding problems, usually one of the following will fix it:
Balance scope
Increase dec slope weight in PHD
Recalibrate

[multiweb (Marc)]

Originally Posted by TrevorW

For some reason tonight I could not get PHD to guide in Dec when pointing east but would guide perfectly when pointing south towards the crux, cause anyone

Your DEC drift is more pronounced when you're close to the celestial equator. If you're way off the SCP (few degrees) PHD won't keep up with DEC drift. If it's more a 'bouncing thing' then check balance and guide only in one direction pushing against the drift. You can now modify this in realtime in PHD v1.12 onwards in the graph window.

[TrevorW]

Thanks Marc
DEC would just drop of the chart when watching the graph
like you said it possibly was more an alignment issue than balance as I did recheck the balance after it starting playing up and seemed OK

[pjphilli (Peter)]

Hi Trevor
I had similar troubles using PHD with my HEQ5Pro mount. I saw on another thread that Stark said that this could sometimes happen when the DEC Algorithm was set for Low Pass Filter. A change to Resist Switching solved my problem completely.
Cheers Peter

[TrevorW]

Thanks Peter, this is fact did cross my mind so I jumped between the two too see if it made any difference, the default is, Resist Switching, but it didn't.

[TrevorW]

Well I'm outside again (rain predicted) and this time I put the scope on my marks did and alignment balanced Ok and PHD is tracking perfectly in the NE at the moment with fluctuations in DEC below 1.

I think it was all an alignment issue probably a degree or two off where the mount should have been pointing.

I'm marking those spots on the ground again for next time

Cheers and thanks for the feedback

[mithrandir (Andrew)]

Originally Posted by multiweb

You can now modify this in realtime in PHD v1.12 onwards in the graph window.

Somewhat off topic, but the new "Star Mass" setting in PHD 1.12.1 is freaking some people out. You can't turn it off, but changing the factor from 0.3 to above 1.0 effectively disables it. The intention is to skip making guiding changes when the atmospherics change suddenly (eg light cloud), but it can take an excessive time to recover, so off seems the best solution until Craig has another look at it.