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Thanks Peter.
I find that focus is easy to achieve with the aid of the Bahtinov mask. I slew to a star nearby the object that I want to shoot. (I'll usually use this as a further alignment point in EQMOD as well). Pop on the mask, and then using a 4 or 5 sec exposure at ISO1600 i can quickly see the diffraction pattern on the laptop screen (im using Backyard EOS). With progressive shots i can then home in on the focus point. I then lock the focus down and slew to the object for imaging. I use a series of 30sec ISO1600 exposures to get the image framing that I want.
Once I've done that I select a guide star with PHD, activate guiding, then do a single exposure at the planned sub time (in this case 8 mins) to check that tracking looks okay. I then dial up the desired sub sequence and i'm away.
In terms of alignment, Im using alignmaster and my procedure there is basically just to run through the alignment process repeatedly until alignmaster tells me I have an alignment error of less than 1 arc minute (ideally less than 30 arc seconds).
Using this procedure I've seen reasonable success so far with subs at 8 mins. (I haven't tried any longer yet, as then next exposure increment in the 400plus firmware hacked intervalometer is 16 minutes, which might be a little long...?)
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