calibrating in phd2

[iwols]

when calibrating is there a certain part of the sky to do it in ,and does the guidescope have to be in a certain orientation,and when eqmod pops up do you have to press the sidereal pop up or anything cheers

[D4N]

Calibrate where you will be imaging.  Normally I slew to target, plate solve, sync, re-slew, calibrate.  Only time I wouldn't do that is if I am drift aligning in which case I would calibrate in the South at the equator then after alignment recalibrate where I will be imaging.

Guide scope should be aligned to the imaging scope.

The mount must be trackinging to be able to calibrate.

[iwols]

 do you have to press the sidereal pop up or anything cheers

[D4N]

I don't have a mount that uses eqmod so I can't say for sure but if that is what starts the mount tracking at sidereal rate then yes.

[alacant]

Hi. If you are using eqmod, you need calibrate once only near the equator and then slew to where ever you want to image. Yes. In eqmod you must first UNPARK and then hit Sidereal. If you are guiding st4 you must calibrate on each target you image. HTH.

[Atreta]

15 hours ago, alacant said:

Hi. If you are using eqmod, you need calibrate once only near the equator and then slew to where ever you want to image. Yes. In eqmod you must first UNPARK and then hit Sidereal. If you are guiding st4 you must calibrate on each target you image. HTH.

Great news. I didn't know i had to recalibrate for each target,  i hope that helps with my problems guiding too.  

[alacant]

The guide-scope can be any orientation. So the star movement makes sense however, align it with the maker's name or whatever vertical at the home position- HTH

[StuartJPP]

It is easier to fault find/diagnose issues if you align your guide scope to your main imaging OTA...I just use a Sharpie line to do that.

Of course it isn't strictly necessary as that is what the calibration sequence is trying to determine.

[D4N]

Generally if the targets are close you shouldn't need to recalibrate, if it's the other side of the sky though there is a good chance it will throw a wobbler unless tell it you flipped or recalibrate.

 

Whilst in a perfect world guide scope alignment would have no effect on guiding accuracy a misaligned guide scope will induce field rotation if your polar alignment is not perfect (and who's is?).  The amount of field rotation will depend on how far out of alignment they are and how bad your PA is.  In normal situations it would not be noticeable on a single sub but if the alignment is a long way out you will have trails.

It would also be noticeable in stacking if you haven't set the software to account for rotation.