Teledyne Photometrics Kinetix truncation error of exposure time in Sensitivity mode

[dstoychev]

The new Kinetix camera from Teledyne Photometrics has an issue where in Sensitivity mode the PARAM_EXPOSURE_TIME parameter reports 1 unit less than what the actual exposure time of the camera is. This is because of truncation error, as confirmed by engineers from the company, and it doesn't affect all exposure times. Here is a non-exhaustive list of times which have been confirmed to trigger the bug: 12ms, 48ms, 75ms, 100ms. To illustrate the issue, if an exposure time of 100ms is specified, the camera's internal timing system will use 100ms but the PARAM_EXPOSURE_TIME parameter will report 99ms.

Manufacturer is aware of the issue and it may be addressed in future firmware updates.

[carandraug]

For reference, here's the reply from Photometrics (see python-microscope/microscope#205):

Just a little update. We have been able to duplicate the same behaviour on our cameras as well.
The camera is reporting exposure time in nanoseconds. At 100ms of exposure for the sensitivity
port (this is observed only for the sensitivity port), the camera reports 99.997938ms. The PVCam
doesn’t round it up but shows only value before the decimal point.

Engineering is looking into it. Unfortunately, the fix will take a while. We will update you again once
we know something more.