Tecnai T12 - User Manual

Revised 03/25/2020 1
Tecnai T12 Operating Procedures
I. Initial Procedures 1
II. Accelerating Voltage 3
III. Specimen Loading and Holder Insertion/Removal 3
IV. Emission Current 7
V. Alignment 7
VI. Camera Control and Imaging 14
VII. End of Session 16
VIII. Troubleshooting 17
IX. Addenda 22
I. Initial Procedures
1.) Check that the “Vac.” and “HT” buttons are lit on the microscope control panel
(check with the room lights on; the buttons automatically dim when the room is
dark). If “Vac.” is not lit, contact the EM staff. If “HT” is not lit, press the button
to light it and proceed normally but make a note in the instrument log.
2.) Log in with the username and password created during training. If the vacuum
logger is running, close it and log off vacuumuser first.
3.) Sign in to the CharFac reservation system and the paper logbook.
4.) Launch the Tecnai User Interface and Digital Micrograph programs.
5.) Check that the microscope status reads
“COL. VALVES” and that the “Col. Valves
Closed” button is pressed (buttons appear
yellow when active).
6.) Fill the cold trap with LN2. The first Dewar
flask of the day should last ~30–40
minutes. Later dewars will each last 2–3
hours. Do not allow the cold finger to
warm or the vacuum will deteriorate
significantly.

Summary

Initial Procedures

Accelerating Voltage

Specimen Loading and Holder Insertion;Removal

Sample Holder Removal

Detailed steps for safely removing the specimen holder from the airlock.

Specimen Loading

Procedures for placing a specimen grid into the holder and securing it.

Sample Holder Insertion

Instructions for inserting the loaded specimen holder into the airlock.

Emission Current

Alignment

Finding the Beam

Steps to locate and confirm the presence of the electron beam.

Gun Tilt

Procedure for adjusting the gun tilt to optimize beam brightness.

Gun Shift

Steps to align the beam using gun shift controls for stable positioning.

Centering the Condenser Aperture

Process for centering the condenser aperture for proper beam illumination.

Condenser Astigmatism

Correcting condenser astigmatism for a symmetrical beam shape.

Specimen Height Adjustment

Adjusting specimen height to align with the eucentric plane.

Beam Tilt Pivot Points

Adjusting beam tilt to minimize movement during focus changes.

Beam Shift

Procedure for centering the beam using beam shift controls.

Rotation Centering

Aligning the image center for high-resolution imaging by minimizing rotation.

Objective Aperture Centering

Centering the objective aperture in the diffraction plane.

Objective Astigmatism

Correcting objective astigmatism using FFT analysis for circular rings.

Camera Control and Imaging

Camera Operation

Controls and modes for operating the CCD camera.

Saving Images

Procedures for saving acquired images to storage.

Dark and Gain References

Creating and applying dark/gain references to correct image artifacts.

End of Session

Standard Shutdown Procedures

Steps to prepare the microscope for the next user.

Last User Shutdown Procedures

Additional steps for the last user, including cryo cycle and logging.

Troubleshooting

No Beam Visible

Steps to diagnose and resolve issues with no electron beam detection.

Control Pad Unresponsive

How to re-initialize unresponsive control pads and check for side effects.

Objective or SA Aperture Not Found

Methods to locate missing objective or SA apertures.

Images Contain Artifacts

Ensuring dark and gain references are applied to prevent image artifacts.

Stage or Beam Shift Trackball Unresponsive

Adjusting trackball sensitivity to resolve unresponsiveness.

MF Knobs Do Not Move Diffraction Pattern

Verifying MF knob assignments for diffraction shift.

Specimen Drift

Reducing specimen drift caused by environmental factors or sample instability.

Other Problems

Guidance on restarting software and logging out to resolve unexpected behavior.

Addenda

Remote Access to Saved Images

Instructions for accessing saved microscope images remotely via SFTP.

TEM Discussion Lists

Information on subscribing to mailing lists for instrument updates and communication.

Tecnai T12 Specifications