Table 3.

Troubleshooting guide for microscope parameters

Problem	Possible Cause	Possible Remedy
Specimen moves while imaging	Poor contact with mounting substrate	Press specimen more firmly on surface of mount
	Poor contact of specimen to mount	Apply conductive paint around specimen to improve contact
Excessive charging of sample	Inadequate bulk conductivity	Decrease number of electrons entering sample or Increase number of electrons exiting sample (See Supplemental Table 1)
	Specimen oxidized
Image appears stretched	Astigmatism from contaminants	Stigmate aperture
Unable to stigmate	Misaligned objective aperture	Center beam and aperture