PART 2: Getting started
First things first, you need to get PHD2 ready to use for drift alignment. You will need to start it up, point at a star near the
meridian and celestial equator (for azimuth alignment, which the drift align wizard defaults to on startup), and calibrate PHD.
Calibration must be performed before doing drift alignment. If you forget to calibrate, the drift align wizard will only
momentarily display a message in the status bar indicating that calibration is required for the wizard to work.
After calibrating, choose a high SNR star (over 10) within the middle quarter of the frame. It is important to choose a star
here, as when you start adjusting, the star can move in any direction in the frame, by as much as a quarter of a frame initially.
Picking a star near the edge could result in adjustments moving the star right out of the frame.
Before starting the drift alignment wizard, you should make sure that bookmarks are enabled (shown), and that you delete any
existing bookmarks. This will assure that you don't end up confused abot which bookmarks mean what (especially if you had tried
to drift align earlier, and ended up needing to repoint the mount.) It probably goes without saying, but saying it anyway for
good measure: Make sure you are pointed a bit ahead of the meridian, and any of your mount's stop limits, so you have time to
perform drift alignment without running into a meridian or horizon limit during the process. It also helps to make sure that
there are no trees or other obstructions that might find their way into the frame while your aligning.
Finally, set your exposure time to 1 second, so you can see an immediate response to any adjustments you make. It also helps to
set the history period to 200 ticks, and the y axis to 8. I've found that these settings are best for early drift checks...later
on, when you require longer drift checks, you might want to up the period to 400 ticks.
Once all the above things are done, your ready to start the drift alignment wizard. You can find it in the Tools menu, Drift
Align. You should see a window like this appear when clicking on that menu option:
The Scope Pointing feature will only be accurate if you are using ASCOM Pulse Guiding. If you are using an ST-4 cable to connect
your guide camera to the ST-4 guide port on your mount, the information here will not be accurate. If you are using ASCOM Pulse
Guiding, you can even control your mount from within the PHD2 drift align window, and it will show you how close you are to the
meridian and celestial equator, making it very easy to get right on top of it for really good drift check.