Is it possible you have that camera in a >8-bit mode? Once you are over 8-bits, to display the image there must be some mapping done since your system cannot display more than 8 bits per color plane. Typically the default mapping is to dynamically map the range of the current image's content to stretch over the full 8-bit range. If it mapped the whole 10/12-14/16-bit range into 8-bits you might have a hard time seeing the image. The downside is that has the min/max pixel values in the image change, the dynamic mapping is changing which means you'll see intensity changes in the whole image.
One way to address this (if it is your issue) would be to turn off the dynamic mapping and assign some fixed mapping that is appropriate for your camera and situation.
Eric
