Check whether the reported current changes from 0.0mA to about 25mA, indicating power to the lights. In this case, you are seeing reflected light resulting from the intense ThAr emission lines. After an image is taken, it will not read out. It must be run on a 24-bit display. The computer is very slow to respond to input.
Solution Go to a local window on the computer.
This will list all processes owned by hires accounts. If, for example, you are using the hires2 account and the output of the above command shows that jobs are running under the hires1 account, then you should stop these other processes as described in the next step.