[lazjen (Chris)]

Originally Posted by RobF

I'd be interested to hear more about this option Chris?

Here's a tutorial on setting up Astrotortilla (AT): http://www.lightvortexastronomy.com/...e-solving.html

I'll quote the manual as it describes the process:

4.3.2 Polar Alignment

Using a plate solver eliminates the waiting that’s distinctive in polar aligning your mount with the traditional drift method. Just solve a frame, turn the scope along RA and solve again. The difference in solved declination values is equal to the amount of drift in declination observed when tracking a star for a time equal to the amount turned.A tedious 20 minute drift can now be done in way less than a minute!

A pair of frames shot at the east/west meridian is used to determine the altitude error of the polar axis, and a pair shot at the southern meridian (assuming northern hemisphere observation) gets you the azimuthal error.

To use the tool, select Tools → Polar Alignment. Choose the correct hemisphere and point your mount roughly at the meridian to measure azimuth error or to the east or west to measure altitude error.

Then press the according button to let AstroTortilla shoot and solve the pair of frames. When done, your polar alignment error in degrees is shown on the screen. Use this to correct your alignment by turning the alignment knobs on your mount.

When measuring azimuthal error, be sure not to point within a half a degree or closer to the meridian to avoid meridian flips! Pointing on the west (right) side of the southern meridian is the safest bet.

I use AT with APT to acquire the images, but there are a few other choices available.

Since I can see SCP, I've switched to using SharpCap's PA routine and will be trying a new PA tool in PHD2 (not the drift align tool) sometime in the future. However I will fall back to this tool if I'm at a location where I can't use SCP.