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Hi Damien,
In what direction are your stars actually trailing? I assume your shooting through the ED80 at 600mm focal length?
Can you see the oblong stars on the camera screen or only when zooming in or on a big screen?
If your mount is roughly polar aligned and set to track in the Southern Hemisphere, than a slight misalignment it should not be too noticeable in a 10sec exposure.
The Goto alignment feature has zero effect on the mounts tracking performance as this is only governed by pole alignment and correct hemisphere entry. but the mount can track
a) in sidereal on northern hemisphere
b) sidereal on Southern Hemisphere
C) in lunar both ways as above
d) in solar both ways as above
To better understand what’s going on, it would be helpful to find out in which way your mount actually tracks
Perhaps take try to align the mount with the aid of a phone app to seek out the pole location and use the phones inbuilt inclinometer to judge the pole height (the markers on the mount are not reliable and more decorative).
Then, choose a star in the east 90deg in declination (dec axis perpendicular to RA axis) and expose once at high ISO for a second or so, to see the stars location in your frame as a reference point. Then expose for while the mount is tracking for something long enough to produce a clear star trail in the image, say a minute (maybe chose ISO 400 if you combat light pollution).
The resulting image will be upside down when shooting through your Ed 80. If your star trail marches mainly east, then you’re tracking in the wrong hemisphere. So the problem is in your information provided to the mount. Any other direction means an error in polar alignment.
The ability of the synscan controller to complete an alignment routine to sharpen up the GOTO is limited to a relatively small polar alignment error. I don’t know exactly how much misalignment it can tolerate. But Beyond the this tolerance in degrees, it will just make wild guesses as to where it is pointed. If you then also track for the wrong hemisphere it will go haywire.
Have you had an instance where the scope tried pointing to the ground? Is the 2 or 3 star alignment feature offering you stars in the northern hemisphere?
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