When the telescope is pointed near the pole, the apparent motion of the stars slow down. This can be easily seen by noting that Polaris is almost stationary. Unfortunately, this variation in speed affects the calibration of the autoguider. If you calibrate at the equator and then move to a polar region, the autoguider will compensate too slowly in RA. If you calibrate near the pole and then move to the equator, the autoguider will badly overcompensate. Either situation can lead to poor guiding.
The obvious way to overcome this is to recalibrate prior to each exposure. This is time-consuming and largely unnecessary. The recommended procedure is to calibrate once and use the Declination field to adjust for the position of the telescope.
When you first calibrate, you should do so on a star near to the equator. Enter the declination of the calibration star in the Declination field. When you move to a different position on the sky, reset the Declination field to match the new telescope position. MaxIm DL will now automatically adjust its calibration to compensate for the change in telescope position. Whenever you reposition the telescope, adjusting this field to match the declination of the telescope will eliminate the need to recalibrate.
If you have an active link to a telescope in the Telescope Control window, the Declination field will be automatically filled in for you.
When using German Equatorial mounts, it is necessary to rotate the telescope 180 degrees to switch between East and West. This affects the calibration of the guider since it reverses the apparent direction of motion on the RA axis. The Pier Flip control can be used to compensate for this if the X axis outputs are connected to the RA axis of the telescope (the usual convention). Simply toggle this control when you flip the telescope over the mount. Auto Pier Flip handles this automatically, if the Observatory Control window is configured properly.