Hello,This night was clear finally, so I used the scheduler to capture NGC7822, 3h en Ha and 3h in OIII. I created sequences for Ha and 0III:
Exposure 240 sec no delay with ASI183MM Pro
Number : 45
Gain: 120
Offset:40
Image for alignment
Track, Align and guide only, no focus.

I launched the scheduler at 19h40: slew to the object, alignment, starting guide and capture. All seemed OK. This morning, I transferred the images from the SDcard of the RPI4 on my PC. 45 images in Ha and 45 images in OIII. But the size of the images, instead of 40 Mo was only 299 Ko ! It seems that only the FITS header was saved. I made a try this morning with the same result: 299 Ko.

I join the file sequence, one image and the log

Kstars V3.5.5, Ubuntu 20.04.3LTS 

Thank for your help.
 

Issue closed. It was a sdcard default. I change it and my sequences are going on as usual thie evening.

I have examined the sequences files and I find out that the value W=40 instead of 5496 ! I don't what could occur !