ASI 6200 download time
Posted: Fri Nov 03, 2023 4:09 pm
I'm pushing to limits my ASI 6200 MM camera to get the highest framerate. I save to FITS format full resolution (62 Mpix!) 16 bit to my PC SSD internal drive. I look at the "DATE-OBS" field and I compute dt=time(n)-time(n-1)-exp(n-1), so dt is the effective dead time between two exposures.
I found that dt=786 ms for 0.1 ms series of exposures, but when increasing exposure e.g. to 512 ms, I measure a dt=274 ms that is exactly 786-512. Real measured dt of many exposures have small deviations +/-0.020 ms, but the average is the above value.
Up to now it is all ok.
But problems arise when I change exposure time between series of exposures. The dt of the first shot with changed exposure value is sometimes the 786 ms (same as above) and sometimes 1572 ms (the double).
Example with the double:
T [ms] dt [ms]
0.1 -
0.1 786
0.1 786
11 1562*
11 776
11 776
512 1060*
512 274
512 274
0.1 1572*
0.1 786
0.1 786
The * values sometimes are lower, and I cannot understand why. Most of all I'd like to get a method to get always the shortest dt as possible. And also a constant behaviour would be important for me because in a long sequence with many exposure changes this results in a random total time duration.
Any help?
Regards,
Lorenzo
PS: example of SCS sequence I used:
LIVE MODE
SET EXPOSURE TO 0.0001
CAPTURE 3 LIVE FRAMES
SET EXPOSURE TO 0.011
CAPTURE 3 LIVE FRAMES
SET EXPOSURE TO 0.512
CAPTURE 3 LIVE FRAMES
SET EXPOSURE TO 0.0001
CAPTURE 3 LIVE FRAMES
STILL MODE
I found that dt=786 ms for 0.1 ms series of exposures, but when increasing exposure e.g. to 512 ms, I measure a dt=274 ms that is exactly 786-512. Real measured dt of many exposures have small deviations +/-0.020 ms, but the average is the above value.
Up to now it is all ok.
But problems arise when I change exposure time between series of exposures. The dt of the first shot with changed exposure value is sometimes the 786 ms (same as above) and sometimes 1572 ms (the double).
Example with the double:
T [ms] dt [ms]
0.1 -
0.1 786
0.1 786
11 1562*
11 776
11 776
512 1060*
512 274
512 274
0.1 1572*
0.1 786
0.1 786
The * values sometimes are lower, and I cannot understand why. Most of all I'd like to get a method to get always the shortest dt as possible. And also a constant behaviour would be important for me because in a long sequence with many exposure changes this results in a random total time duration.
Any help?
Regards,
Lorenzo
PS: example of SCS sequence I used:
LIVE MODE
SET EXPOSURE TO 0.0001
CAPTURE 3 LIVE FRAMES
SET EXPOSURE TO 0.011
CAPTURE 3 LIVE FRAMES
SET EXPOSURE TO 0.512
CAPTURE 3 LIVE FRAMES
SET EXPOSURE TO 0.0001
CAPTURE 3 LIVE FRAMES
STILL MODE