Faraday Cup Measurment Notes¶

• plug in
• wait 1 hour
• activate ZCHK (maybe already when turned on) (should say ZC on screen)
• plug into faraday holder
• set to lowest range (2nA)
• activate ZCOR to set zero (should say ZZ on screen)
• set auto range if desired
• deactivate ZCHK to begin measuring
  • 1.00 nA

Exposure Time to Screen Current measurment¶

• refer to Tecnai Help for "Exposure Time, Plate Camera CP"
• formula: beam current (nA) = 2.15 * emulsion / measured_exposure_time
  • exp time is between 3.1 and 3.5 depending on size of beam
  • emulsion = 1
  • beam current is between 0.61 and 0.69 nA