Changes
/* User's Troubleshooting Guide */
'''If the rear-of-slit (ROSCam) camera window does not produce any images (though the exposures seem to count down), it probably needs a reset'''
* Check that you've got the light path right: guide fold mirror centred out of beam and the rear-of-slit mirror in the beam
* Then check that it's not an image scaling issue, by turning on the slit illumination (which is bright enough to show up under most circumstances)
* If you still don't see anything:
