After a crash

After a crash, you will of course have to use quite a bit of judgement based on the circumstances of the crash. However, some general suggestions for things to do might include:

• If there's a chance that the OSA and/or ZP got bumped, you're probably best off examining both using the VLM to make sure that they're happy.

• If you might have bumped the piezo stage and want to check its health, the simplest thing so to use the Move menu of the SM program to move the piezos over their range. You can then monitor the capacitance micrometer output on the front panel of the PI controller, which puts out 1 volt per 10 $\mu$m of motion (need to check!). Note that if the piezos cannot stay ``in servo'' (i.e., cannot reach a desired position with the capacitance micrometer), the ``blah blah'' light is illuminated on the PI piezo controller. Momentary flashing of this light at the end of a scan line is normal; steady illumination of this light is not. Another good check of the piezo stage health is to use the VLM to view a sample as it is scanned.