Using the JEM-1010 Transmission Electron Microscope for thin resin sections of biological material
Inserting the sample:
- Ensure the HT and filament are turned off
- Pull the specimen holder straight out until it won’t go any further, then gently turn it anticlockwise until it stops
- Very gently pull the specimen holder out and rest it on the stand. Make sure you never handle past the O-ring area towards the sample end
- Carefully flick up the lever at the sample end with forceps
- Load the grids into the specimen holder (dull side up; i.e. sample side up) and gently lock in place with lever
- With a flat palm, push the specimen holder in softly so that the guide pin (on left) fits into slot. The green light at right will come on.
- After the vacuum has pumped through one cycle the green light will go off.
- Turn the specimen holder clockwise a quarter of a turn. It will stop. Do not force it further.
- Guide the specimen holder in gently.
Initial viewing of an image:
Check HT i.e. if it needs changing. If so then:
- Turn OFF HT (never change HT with HT on)
- Type ‘htset 80’ <enter> (for 80 kV)
- Alternatively, ‘htset 100’ <enter> (for 100kV)
- Turn HT ON (it will light up when pressed)
- Wait for beam to stabilize (53 µA for 80 kV)
- Turn filament ON
- Chamber screen should now be filled with green light.
- If there isn't any light, ensure the camera is out (press red light on camera control); check that the magnification is not extremely high; or possibly a grid bar is blocking the beam.
- To find your sample on the grid, press LOW MAG and move out the objective aperture by turning the silver lever to the right and you will see the full grid.
- Using the big white wheels (left and right of column) move your sample around, find the area you want and bring it to the center on the screen.
- Move the objective aperture (on column below sample port region) in by turning the silver lever to the left.
- Press MAG 1 and spread the beam (brightness knob on left hand side console).
- Realign the objective aperture.
Things to check:
Objective aperture (located on column below sample port region)
- At around 5000x mag. adjust the brightness knob (left hand console) to create a small bright circle.
- Press DIFF (right hand console) and you should see a bright circle in the centre of a dull circle.
- If not, center using the objective aperture two knobs.
- Press MAG 1 and spread the beam.
Condenser aperture (the top adjustable aperture on the column)
- Should be set at largest.
- To change, turn large condenser knob with dots on it to appropriate setting.
- If not aligned then the beam swings across the screen when brightness is changed.
- To correct, adjust the brightness knob (left hand console) to create a small bright circle.
- Centre the beam with SHIFT X and Y (left and right hand consoles) then spread beam clockwise until it is nearly the same diameter as the screen by turning the brightness knob (left hand console).
- If off center then use the condenser aperture knobs to correct position on screen.
Grid height and Wobbler
- With camera in, at around 50,000 to 80,000 mag undertake the following:
- Check to see that the objective lens current is correct (page 6 on microscope computer screen). i.e. 3.85 at 80 kV. Use focus knob on x16 (right hand console) to adjust the number.
- Focus using the z-knob (small knob directly under the specimen holder).
- Take out the camera.
- Set mag, to 3000 to 5000x.
- Using brightness knob (left hand console) bring beam to a small bright circle.
- Press X Wobbler (right hand console).
- Use Wobbler knobs under the Perspex cover (right hand console) to bring both spots together on screen.
- Turn off Wobbler.
- Spread beam (brightness knob – left hand console).
- This should be around 1 (large) if the sample is stable or 5 (small) if drifting.
- To change, bring beam to a bright circle using the brightness knob (left hand console).
- Use the flat buttons (left hand console) to choose a spot size.
- If the beam moves across the screen then re-center using SHIFT X and Y (left and right hand consoles).
Hints for objective astigmatism adjustment at magnifications greater than 80,000x
- Press Obj Stig (left hand console) button and use Def X and Y (x16 if course adjustment required). [Def = deflector]
Bring microscope to neutral astigmatism position by ensuring both green lights on Def X and Def Y are lit.
- Whilst looking at image and using Def X, Def Y and focus (one at a time) create best image possible.
- Whilst looking at the RTFFT (Real Time Fast Fourier Transformation) panel on computer screen and using Def X, Def Y and focus, create the largest and roundest circle possible.
Changing objective aperture sizes
- Camera OFF and out.
- With the sample IN, at around 5000x mag, adjust the brightness knob (left hand console) to create a small and bright circle.
- Press DIFF (right hand console). You should see a bright circle in the center of a dull circle.
- Change aperture using the spots on the side as a guide to size.
- Ensure the bright light is in the center of the dull light. If not, center using the black objective aperture knobs (at front and right of aperture knob).
- Press MAG 1.
- Spread the beam (brightness: knob on left hand console).
End of session
- Camera OFF and out of chamber.
- Condenser aperture at largest (1).
- Magnification under 15,000x.
- Spot size at 1.
- Turn filament and HT OFF.
- Remove grids and replace sample holder into microscope.
- Close the digital capture system (ITEM), turn off computer screens, replace over on screen port and turn HT on.
Last client of the day:
- Turn HT off.
- Scroll brightness on screen down.