When you select a bias frame in MaxIm DL the exposure time is automatically set to the minimum that the camera supports and therefore the exposure time selector will be "greyed out" and you can't change the time.
Whatever exposure time is currently selected In the exposure time window is ignored once you select the exposure "Frame Type" to "Bias".
When you connect to a camera driver in any capture program it should read the capabilities of the camera and not allow you to select a shorter exposure time for Lights and Flats than the camera can deliver and for QSI 683 WSG with the mechanical shutter that is 0.03 seconds, I assume that you meant to write 0.03 secs in your topic and not 0.3 secs that you have written.
But, as mentioned above, once you select the frame type "Bias" then the camera will be asked to expose with the shutter closed using the minimum readout time for the sensor, completely independently of the minimum exposure time that is normally applicable when the shutter is being used.
Lastly, you can verify that the bias frames are being taken with the correct "zero" exposure time by inspecting the .fits header for the image after you have taken a bias frame.
In MaxIm, with a new bias frame opened on the desktop, select from the "
View" menu at the top of the MaxIm desktop "
Fits header window" and in the "
View" tab of the fits header window look for the fits keyword(s) EXPTIME and/or EXPOSURE, one or other or both may be present, and the actual exposure time of the bias frame will be recorded.
For a typical QSI 683 camera that will be recorded and displayed as shown in the screen-grab attached below.
Will.
WILL B