This control is enabled or disabled depending on the capabilities of each individual mount. Clicking the Mount info button in the status bar will show if PPEC is supported for the mount.
PPEC (Permanent Periodical Error Correction) – Checkbox to turn on or off PPEC. The grayed out timer will turn yellow when training is in progress. For more information see the PPEC section of this document.
Permanent Periodic Error Correction (PPEC) allows the mount to correct the right ascension (RA) for manufacturing errors in the worm wheel. PPEC Training your mount will take small movement corrections and store them within the mount. These corrections are then played back as the RA moves when PPEC is turned on.
How to PPEC train your mount – Before starting a training session your mount should be able to track and guide at a stable rate. When you are happy with the way in which the mount is guiding and you thinks its stable and consistent, start a guiding session near the meridian and let it stabilize. Start the PPEC training session by clicking the PPEC Train checkbox. When the mount starts collecting data the timer icon will turn yellow. The mount will continue to collect data for several minutes. When finished the timer will turn gray and the PPEC Train checkbox is unchecked. You can now start and stop the PPEC replay using the PPEC checkbox. It’s recommended that you use PPEC for any future tracking or guiding sessions. If you’re guiding session worsens turn off PPEC and validate your guiding is back to normal. You can retrain the mount at any time as long as the tracking is turned on.
PPEC on/off checkbox – Turn on or off playback of corrections
PPEC Training Checkbox – Used to start a new collection session
PPEC Data collection icon – Indicates mount is collecting error correction data
When using PHD2 for guiding it’s recommended to turn off PPEC during the PHD2 calibration process and turn it back when finished.