12:48
Try to optimise gun. Want sharpest possible increase in I vs E. Also try to get maximum I.
Angle of sample 135deg. Sample Au on Si (95min, 3.5A, 3-6e-8mbar)

Getting maximum Is
1. Adjust deflection voltage for maximum I at the start of the exponential increase (DAC = 500)
	- Vd = 3.05V, Is = 0.130e-8 A
2. Adjust accelerating voltage for maximum I
	- Va = 38.5V, Is = 0.100e-8 A
	- Note: Is decreased when Va was changed. Va was originally 38.4V. There seems to be a slow increase in current. (at 0.105e-8 A after 30s)
3. Adjust focus voltage for maximum I
	- Vf = 0.00V, Is = 0.120e-8 A (still changing).
4. Adjust venault voltage for maximum I
	- Vv = 15.3V, Is = 0.075e-8 A (changing venault caused significant decrease in Is. Even when venault restored to original value 12.2 V, Is still reduced).
 
Getting sharpest possible increase in Is with E
- Adjust Vf, take sweeps, keep all parameters fixed. Results in folder "focus". Subdirectories indicate the value for Vf.
- Va = 38.5V, Vd = 3.05, Vv = 15.3

Notes:
- Vv should not significantly effect focusing of gun. Greatest effect is on emission current. So do not adjust Vv to optimise focus of gun.
- Ratio of Va/Vf is important for Einzel lens. So only change Vf, not Va.

15:35
Sergey not impressed.
Do loop adjustment instead.