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Finally got to do a serious test last night even though it was a bit rough and ready. I just plonked the tripod down and took a pic and plate solved it. I needed about 8 seconds exposure to get a solvable image. The astrometry program gives results in J2000 so I plugged the results in Stellarium and it gave me back the Azimuth and Altitude. So all I had to do was adjust Azimuth to be 180 and Altitude to be my Latitude. I ended up getting close to the SCP. However, I knew that was illusory as the next test was to see how much collimation error there was. To do this I took an image with the mount rotated 6 hours west and 6 hours east, Plate-solving each one. Rather than calculate the results outside with the mozzies I then retired indoors for some analysis.
Using the plate-solved images with significant objects highlighted I could plot the centre of each image (all 3) onto a single picture. Then joining the dots gives a circle whose centre is where the mount is really pointing. This coincides with the centre of the line joining the East and West images but is useful for future reference.
Next step is to get an image with the mount actually pointing at the SCP as a reference for alignment. Basically the idea is to be able to say if BQ Oct and HIP42708 are horizontal on the image then the image should be centred at...
Alternatively, any ideas for collimation are most welcome
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