PHD2 Guiding for Spectroscopy
Step-by step procedure for using PHD2 with a Slit Spectrograph:
- Open PHD2, Connect Equipment, Loop exposures,
- Enable the slit overlay: View menu, Spectrograph Slit
- From the View menu select Slit Position. Adjust the slit position overlay (red rectangle) so that it matches your actual slit position. PHD2 will remember the slit position so you only need to do this once.
- Move the star close to the slit. Use your mount's hand paddle and/or PHD2's Manual Guide tool to move star approximately to the desired position. It does not need to be precise yet.
- Select the star by clicking on it, then click the Guide button to start guiding.
- Select menu Tools, Adjust Lock Position.
- Move the lock position to the desired position at the center of the slit. You can start with large steps, then use smaller steps to move the lock position with sub-pixel accuracy. Enable the Sticky Lock Position option. Click Save to save the lock position for next time and close the Adjust Lock position window. You are now guiding with the lock position at the desired location on the slit.
In your next session the process is simpler:
- Start PHD2, connect equipment, loop exposures
- menu View, Spectrograph Slit
- Use your mount's control pad to move the star somewhere near the slit (exact location is not important)
- click on the star and start guiding
- menu Tools, Adjust Lock position
- click Restore
- PHD2 will then guide the star onto the precise saved location at the center of the slit