scheduler: if guide star is lost, obtain another #34925
If the guide star is lost would it be possible to obtain another star and continue capture?
As can be seen here at around 22:18:
As it is now, if the guide star is lost, that's the end of the session and no more frames are taken.
scheduler: if guide star is lost, obtain another #35908
Hi. Here is the response from the phd2 guys:
'We think recovery from this sort of problem needs to be done either manually or by the imaging app. If PHD2 tries to relocate a new guide star somewhere else on the full camera frame, the lock-point is going to move by a substantial amount. So whatever you were trying to image is going to be badly positioned in the frame or may be outside the field of view altogether. If the imaging rig has a rotator, the imaging application can locate a new guide star via plate-solving and then sending commands to the rotator. Neither of those things can be done by PHD2. '
If we could have an option in capture whereby if there is a lost star, it ordered the selection of a new star after a certain set period...?
scheduler: if guide star is lost, obtain another #35910
Hmm.. this is less than half of Bruce response ....
You must understand it is much more easy to avoid to loss the star than to try to recover after it is lost. From my experience the most efficient recovery, if the star cannot be re-acquired by phd2 after some time, is to jump to the next target where there is maybe no cloud and no tree.
In your case it look like the star jump out of the measurement area for some mechanical reason, the last measurement show a 30" offset.
You use the small default value of 15 pixels for this measurement area, if you double the value for "search region(pixels)" to 30 pixels this probably fix the problem because the star can be re-centered and you only lost the current exposure. Sure it is even better if you can fix the source of the mechanical problem.
The log also show some star loss because of star mass change, in this case it recover automatically after some time.
You already increase the star mass tolerance to 80 but it is probably better if you disable it totally.
This two setting are at the top of the Guiding tab in the advanced setup.
scheduler: if guide star is lost, obtain another #35911
I do apologize. This is the rest of Bruce"s message. HTH.
… In some cases, PHD2 may lose the guide star and you'll be alerted by an audible beep and flashing orange crosshairs. There are several reasons this might occur:
1. Something may be obscuring the star - clouds, the observatory roof, a tree, etc.
2. The star may have abruptly moved out of the tracking rectangle because something shifted in the mount/camera/cabling infrastructure - cable snags can cause this
3. The star may have "faded" for some other reason, perhaps because it is overly faint or the camera is not well-focused
Obviously, you'll need to identify the source of the problem and fix it. However, it's important to understand that PHD2 will not start moving the telescope around in an attempt to relocate the guide star. It will simply continue to take exposures and look for the guide star to reappear within the bounds of the current tracking rectangle.