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Hi Colin,
Firstly congrats on setting everything up! And getting TPoint up and running and plate solving. That took me a while. The key being having the accurate image scale.
I take it you did the rough polar alignment first as in the manual? If not do that first to get you close.
So you do your 60 point tpoint run. You click on super model. It comes up with a better RMS (average of the errors). You click apply to apply the supermodel and watch the new RMS figure go lower.
The Polar Alignment report gives you 2 options. How much you need to adjust your RA and Dec or use accurate polar alignment.
So you clicked on accurate polar alignment. It verifies you have done the super model. Then it asks you to slew to a star in the north or the south and gives a little percentage of the existing location. As you move you will see that % appropriate change. I go for about 95%. I usually point to a low star in the north as its easier for my observatory.
Once you have a bright star centred at this location you click commit. The software now moves the mount so that same bright star needs to be adjusted manually to be brought back to the centre cross hairs of your image (you need to activate centre cross hairs so you can see that is exactly centre).
Now adjust the RA and Dec adjustment knobs taking new short exposure to see where it is until you have manually adjusted the mount so that same bright star above is now centred again in the cross hairs. Now click done and the Tpoint model takes into account the physical change you just did.
You should now be very well polar aligned. It should be good enough to image but if you want to take it further perhaps do a 200 or 300 point model and repeat and will get it that little bit closer. 60 point may not be enough to get a really accurate accurate polar alignment but if you watch the polar alignment report which updates as it adds more points it probably won't change much with more points but it does a bit.
I also use 2x2 binning when centring the bright star but I have used 1x1 for that little bit extra accuracy. I would not use 3x3 as it would be too sloppy.
I would do that on another night so you can get some imaging done.
The accurate polar alignment feature is a terrific improvement to the TPoint program.
Greg.
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