I tried KStars 3.5.7, 3.5.8 and 3.5.9 beta. When I start the refresh routine for the polar alignment, after rotation, KStars keeps crashing. The log says "Restarting capture attempt #..." for many times before crash.
Before version 3.5.7 there was any issue and all worked like a charm.
The guider is an "OpenAstroGuider" (IMX290) on a AZ-GTi mount.
I recommend turning on the Alignment logging to see what is going wrong. I suspect it isn't detecting the stars you want, but can't be sure without more information
Restarting capture means it failed to capture from the web cam. Maybe decrease refresh rate to 0.5 seconds, or toggle mean stacking the the V4L2 driver.
I toggle mean stacking and nothing. I set it to 0,5 sec refresh rate and automatically sets to 1 sec. It automatically change the exposure to 1 sec, even if i change it and this is the error log.
I've been searching through the forum looking for the polar alignment issue that I had last night (not easy with a limit of 20 results). In any case, I had an issue with the polar alignment refresh last night that seems similar to the one reported here. Although I did not get any crashes, I did have problems with the FITS Viewer refresh during polar alignment.
The main issue seemed to be that the FITS viewer would not refresh. I went through the PA tool multiple times, I'd get to the PA result, toggle to the full screen FITS Viewer, select a star, Alt-Tab back to the PA tool, click Next then click refresh and although the "Image #" was incrementing every second the FITS viewer was not refreshing the image. Hard to do the alignment without the refresh.
I had used the PA tool the night before without issue so I was trying figure out what I changed to break it. Ultimately it seemed to be related to using dark images. The previous evening I did not used Dark images and earlier in the day I had created a set of new dark images using the Dark Library tool. So, I had enabled the dark check box on the Align tool. As soon as I unchecked the Dark box the FITS Viewer refresh started working again.
Another note, it seems that the KStars 3.5.8 version now has a minimum refresh of 1.0 second. I'm pretty sure I used to use 0.5 seconds with Update PA Error on.
I'm using KStars 3.5.8 on Ubuntu 20.04.4 LTS. Guide camera is QHYCCD QHY5 III 178C.