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Polar scope - most accurate in SH?
Last night I was using my AZ-EQ6 as a guiding platform for my Sony NEX-3 camera, shooting at f/5.6-55mm. This motivated me, for the first time, to try out my polar scope, which actually works really well in my dark skies of southern Tassie.
Alignment with the polar scope was pretty straightforward. I typically drift align, and had not adjusted my elevation settings since the last drift session (nor moved my location). But I was surprised to find my elevation was slightly out, at least according to the polar scope. (I did need more adjustment in azimuth, but some final tweaking in elevation was also required).
That got me thinking - how accurate is the polar scope in the southern hemisphere? Although we have the distinct disadvantage of no bright pole star, we do have a fairly distinct Octans asterism that is useful if your skies are fairly dark. (There is also 6.9 mag BQ Oct, which is just visible in my polar scope and is only 10.5' from the pole).
The interesting part here is that the reticle lines up with 4 stars in the SH, not one like in the NH, which in my reasoning should give a much more precise alignment, because there is more 'leverage constraint' in the model.
Anyone agree/disagree? I'm now wondering how accurate I might get my alignment with the polar scope. It's certainly a LOT faster than drift aligning, even when I'm using the beaut PHD2 procedure!
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