Predictive guiding is an advanced guiding concept that averages several guider frames while sending corrections, if any, to the mount at the rate of the incoming guider frames.
Hence every time a new frame has been captured and downloaded from the guider a correction is send to the mount, if any, and the average frame resulting of the stacking is updated.
The corrections for the mount are computed based on the average frame.
Averaging guider frames leads to larger SNR useful for dimmer stars, or patterns.
By sending correction at the rate of the incoming guider frame SKG can efficiently tracks drifts.
One could accomplish the same using a longer guider exposure time, however this means that we will not send any correction to the mount during this time. Eventually long exposures may lead to elongated stars due to inevitable tracking drifts.
With the above technique SKG is able to send corrections at a faster rate to deal with drifts while it accumulates frames (averaging) to boost the SNR, in to minimize any correction latency.
Predictive guiding works best with a good mount having very little short term mechanical noise (gear-boxes). PE or short term mount errors can not be effectively correct with predictive guiding, therefore we recommend, when applicable, to use PEC.
With predictive guiding we can guide with dimmer stars (higher magnitudes).
Predictive guiding is handy for a grab and go configuration to minimize the time in the filed for aligning the mount. If the mount is good then some polar alignment errors, leading to drifts, are corrected by SKG without having to use a single short guider exposure.
To work with predictive guiding you must set reference stack size > 1 and enable the predictive guiding check box
We suggest to use a small stack first. start with 2 frames, then 4, then 8, ...