Krios-K2 Presets used for 2.8 A proteasome reconstruction in 5 hours data collection at SEMC @ NYSBC¶

• Nanoprobe was used to allow smaller beam to be used for multiple targeting on 2 um hole.

Tecnai Krios 300 kV high tension, XFEG, Gun Lens 4 extraction voltage 4100, 70 um C2 aperture and 100 um objective aperture (except when obtaining grid atlas).
Gatan camera dimension 3710(w)x 3838(h) after rotation to Leginon standard. The size of the beam on the scope main viewing screen always covers the 1.2 um hole at en preset on our scope.
Pixel size is 1.10 A at 22500x scope nominal mag.:

Probe	Lens Series	Magnification:	Preset name:	Image Shift (x,y):	Dimension:	Binning:	Camera Dose (e/camera pixel/s):	Exposure Time (ms):	Specimen Dose Rate (e/A^2):	Spot Size:	Defocus (m):	C2 (um):	frame saving:	Camera
micro	LM	100	gr	Aligned	1024x1024	4	n/a	500	n/a	5	0.0	70	no	Ceta
micro	SA	400**	sq	Aligned	927x959	4	8	100	n/a	10	-2e-4	70	no	K2
nano	SA	1300**	hl	Aligned	927x959	4	8	200	0.004	11	-1.5e-4	70	no	K2
nano	SA	22500	fc	0,0	924x924	2	>=8*	500	3.3	8	-7e-7	70	no	K2
nano	SA	22500	fa	0,0	927x959	4	>=8*	250	1.65	8	-1.5e-6	70	no	K2
nano	SA	22500	en	0,0	3710x3838	1	8 e/pixel/s and ~0.7 um on the specimen	7000	46	8	(-1e-6 to -2e-6)	70	200 ms/frame

**These two magnifications are add-on to standard SA lens series.

• Note: If the correlation or power spectrum don't work well enough for the standard Camera Dose Rate of 10 e/pixel/s for fc and fa, you may increase it more so not to have to use longer exposure time. The recommended value in literature is meant to give highest DQE at all sampling frequencies. Using a higher camera dose by 50% will certainly not damage the sensor.

• Note: no defocal pair was acquired in this experiment. Therefore, no ef preset.