We’re using the Argus API to control the exposure and gain of our camera. We were hoping to have a fully automatic approach by setting large ranges for both the exposure and the gain and letting argus decide, but we are running into some issues in low-light settings. Our exposure range is 1/8000 to 1/2 to allow for both day-time and night-time settings, and during the day the image looks just fine. But at night or in other low-light scenarios, we have noticed that the exposure is never auto-adjusting longer than about 80ms.
Our gain range during this testing was 1 to 180. We found that when we just set the gain to 1, or set a small range such as 1 to 2, the exposure time was using the full range (up to 1/2 second in our test). But it seems the larger we set our gain range, the more limited the exposure time becomes.
To set the gain and exposure ranges, we are just using setGainRange() and setExposureTimeRange(). Is there anything we can do to allow for a large gain range and still have the exposure auto-adjust to longer exposures when needed? Are there other parameters we are missing or should be looking at here? Any other tips or suggestions? Note that we have also set our framerate accordingly to accommodate long exposure times.