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- Selected Area: 100 um, 50 um, 20 um, 10 um
- Entrance Aperture : 120 um, 60 um, 40 um, 20 um
Energy Filter
- Slit width at 10 eV : 60 mm on film
- Slit width at 2 eV: 25 mm on film
Expected Values
- Dark Current: 104 uA (12-5-11)
- Emission Current: 179 uA (12-5-11)
- Column / PiG1: 33 uA (12-5-11)
- Camera / PiG3: 30 uA (12-5-11)
- PEG1: 1.5 *10^-5 Pa (12-5-11)
Ice Thickness
The ice thickness was measured by punching a hole on the ice at 30 degrees (tilt) and
measuring the length of the hole at -30 degrees (tilt). Using a collection semiangle of 45mrad,
and assuming that the ice scatters as Carbon, the value that DM gives for the thickness is roughly
half the actual thickness of the ice.
CCD information
- Size of camera : 4096 x 4096 pixels
- Pixel size: 15 um
- Post-film mag : 1.40
- Gain in SerialEM and Digital Micrograph : 29 counts / electron
Part number for replacement balloons
- part #780 208 463
- Used for filling liquid helium
CCD : Signal to noise ratio in comparison to film
Magnification Calibration: Jeol 3200FSC
- Magnifications calibrated using 2160 cross grid using method described in SerialEM documentation
| Film Magnification | CCD Magnification | Unbinned Pixel Size (A) | 2X Binned Pixel Size (A) | Angle of Tilt Axis | Calibrated Film Magnification |
|---|
| LM 100 | 143 | 1046 | 2093 | 206.3 | |
| LM 120 | 190 | 791 | 1583 | 212.5 | |
| LM 150 | 248 | 606 | 1212 | 219.8 | |
| LM 200 | 313 | 479 | 957 | 221.7 | |
| LM 250 | 360 | 417 | 833 | 222.6 | |
| LM 300 | 426 | 352 | 703 | 222.9 | |
| LM 400 | 556 | 270 | 540 | 223.9 | |
| LM 500 | 679 | 221 | 442 | 224.5 | |
| LM 600 | 808 | 186 | 371 | 224.8 | |
| LM 800 | 1,057 | 142 | 284 | 226.0 | |
| LM 1,000 | 1,302 | 115 | 230 | 224.7 | |
| LM 1,200 | 1,574 | 95.3 | 191 | 223.1 | |
| LM 1,500 | 1,965 | 76.3 | 153 | 226.8 | |
| LM 2,000 | 2,650 | 56.6 | 113 | 229.8 | |
| LM 2,500 | 3,442 | 43.6 | 87.2 | 234.9 | |
| LM 3,000 | 4,300 | 34.9 | 69.8 | 238.6 | |
| MAG 2,000 | 2,750 | 54.5 | 109 | 155.6 | |
| 2,500 | 3,439 | 43.6 | 87.2 | 154.7 | |
| 3,000 | 4,160 | 36.1 | 72.1 | 154.9 | |
| 4,000 | 5,574 | 26.9 | 53.8 | 155.0 | |
| 5,000 | 6,794 | 22.1 | 44.2 | 125.7 | |
| 6,000 | 8,050 | 18.6 | 37.3 | 126.0 | |
| 8,000 | 10,841 | 13.8 | 27.7 | 126.2 | |
| 10,000 | 13,798 | 10.9 | 21.7 | 125.2 | |
| 12,000 | 16,598 | 9.04 | 18.1 | 125.8 | |
| 15,000 | 20,741 | 7.23 | 14.5 | 126.4 | |
| 20,000 | 26,806 | 5.60 | 11.2 | 126.1 | |
| 25,000 | 33,962 | 4.42 | 8.83 | 127.2 | |
| 30,000 | 40,859 | 3.67 | 7.34 | 127.3 | |
| 40,000 | 54,074 | 2.77 | 5.55 | 125.6 | |
| 50,000 | 68,165 | 2.20 | 4.40 | 126.0 | |
| 60,000 | 81,221 | 1.85 | 3.69 | 125.8 | 59,717 |
| 80,000 | 106,738 | 1.41 | 2.81 | 125.8 | |
| 100,000 | 132,895 | 1.13 | 2.26 | 125.8 | |
| 120,000 | 157,146 | 0.95 | 1.91 | | |
* Overall CCD to film factor: 1.40
Defocus Offset
- Set defocus to varying values between 500nm and 3000 nm
- Focus at 200,000X, image at 50,000X on CCD
- Defocus determined using ctffind3.
- curve: calc_df = 0.76 * set_df + 36 nm
- df offset curve may 9 2013:
- Set ALLOWTOPICVIEW =
-- BillRice - 28 Sep 2007
| META FILEATTACHMENT | attachment="j3200_df_offset.png" attr="" comment="df offset curve may 9 2013" date="1368656112" name="j3200_df_offset.png" path="j3200_df_offset.png" size="3973" stream="j3200_df_offset.png" user="Main.BillRice" version="1" |
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