Quote:
Originally Posted by jjjnettie
Ok, so I've done a drift align, and everything looks good.
Now Phd is saying it can't callibrate because my star isn't moving enough.
What the???
I thought that was the idea of drift aligning?
Any ideas what the problem may be?
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Drift aligning can come later. First you need to convince PHD it knows what's going on.
Did you check in the brain settings that:
"Dec guide mode" is right? Auto is probably best unless your mount is spot on.
"Max dec duration" is big enough? 2000 is usually a good value.
"Calibration step" is right for your focal length. 2500 works well on my 500mm guide scope
The pulse length is the maximum PHD will use. If a smaller amount works, it will not use the maximum.
Once you get it to calibrate, fire up "Tools->Enable Graph" and see how well it is tracking. A small sawtooth is normal. A big one means your alignment is not as good as you though it was.
If the camera is square with the mount, you can drift align by turning off the Dec motor, turning PHD's grid on, selecting "loop for frame and focus" and watch where the stars go. It takes some practice (I'm not that good at it), but does work.
Quote:
Originally Posted by multiweb
I think PHD doesn't care about the orientation of the camera. I remember Craig Stark saying that in one of his posts a while ago. That's the best thing about it. It doesn't care where North, south East or West is in the camera FOV. I'm pretty sure though that calibration is to know how far the mount moves for a known pulse time. pemPRO calibration works exactly the same way. The program needs to know how far the mount is going to move so then it can scale the pulses for known deviations while guiding. That's my understanding of it anyway.
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PHD wants to work out which in direction RA & Dec movement commands move the stars. It doesn't care what the orientation is. If moving the mount only in RA causes the stars to move at 45 deg, that's probably fine. Making it square to the mount just makes it easier for you to make sense of. After all, how would you make an off-axis guider work if you could not find a star without using some strange orientation?
Quote:
Originally Posted by multiweb
One thing I've noticed with PHD, if it starts doing stupid things. Shut it down. You don't have to reboot your PC, but disconnect the USB on the guider, then replug the camera. Restart PHD and voila! It should start working fine again.  |
If PHD won't shut down disconnect the guide USB and try again. If it still won't die, kill it from task manager.
... or did I? 
And we're guiding.
