With PHD2 - the calibration time issue remains - but I’m not so clear about whether PHD2, like Maxim DL, normalizes the calibration figures, taking into account the DEC of calibration and guiding. With SGP being so effective at meridian flips, its worth fully understanding the behavior of the SGP-PHD2 relationship for start of sequence events too.
PHD2 takes into account declination based on where you calibrated and applies a bias. I don’t know the math. You might post over at the PHD2 Google Group if you really want to know what they’re doing exactly. They’re very active.
SGP has little input into what PHD2 is doing. It basically issues commands to the server and waits for a response back from the server. It used to do much more before they improved their socket communications; however once Andy/Jared/Ken started collaborating, things improved dramatically from there to the point that PHD2 is doing all of the work. If you’d like to see more about it, go to the Yahoo Group and do a search for PHD2. There are quite a few threads on it.
1) Does the manual override instruct PHD to look out for pier side and work out when to reverse polarity for itself?
Andy would be best to answer this. You might PM him.
2) Does 1) affect SGP meridian flip feature afterwards - will it flip again?
I flip back and forth every night, no issues with PHD2 guiding. It uses SideOfPier to figure out when to flip the data and uses the connection inside of PHD2 to the mount to figure that out.
3) Does PHD2, like Maxim DL, normalize the calibration figures back to DEC=0, taking into account the DEC of the calibration and the DEC of the guiding
PHD2 does take into account declination. How and why were spelled out in the PHD2 Google Group. I’d head over there and ask if you want the nitty gritty.
I don’t have issues calibrating PHD2 like I sometimes did in PHD1. I also find that PHD2 isn’t sensitive to where you calibrate as long as you’ve done it.