The 10 bit image is stored as a 16 bit image, which IMAQ converts to 8 bits for display. The conversion method is controlled by the function IMAQ WindDisplayMapping, found in the Display palette.
The default method is Full Dynamic, which converts the full range of the 16 bit image to an 8 bit image. The largest value in the 16 bit image is mapped to 255, and the smallest is mapped to 0.
You can select Downshift to force a fixed conversion. Read the help to get more details about how to use it. For a 10 bit image, you should downshift 2 bits to retain the most significant bits.
I'm not sure about the occasional noisy image issue, unless it is a side effect of the dynamic mapping. Try Downshift mapping and see if the problem goes away.
Bruce
Bruce Ammons
Ammons Engineering