Day 2 - Remote Diffraction Acquisition in STEM - Duscher

Value of the Information & Strength of the Argument

The video provides valuable practical insights into the operation of a STEM for CBED acquisition, including real-time troubleshooting and adjustments. The argumentation is based on direct observation and experience, with clear explanations of the phenomena observed. The presenter demonstrates a deep understanding of the physics involved, such as excitation errors and the effects of convergence angle on diffraction patterns. The value lies in the authentic, hands-on demonstration that bridges theory and practice, though the informal style and occasional technical issues may reduce the clarity for less experienced viewers.

Scientific Rigor, Source Quality, Title Accuracy

The scientific rigor is high, as the presenter is an expert and the demonstration is based on established principles of electron microscopy. However, no external sources are cited in the video or description, so the quality of sources cannot be assessed. The title accurately reflects the content, which is a remote diffraction acquisition session. The video is a tutorial/demonstration, and the lack of formal citations is typical for such content, but it limits the ability to verify claims independently.

The title accurately describes the content: a remote diffraction acquisition session in STEM, led by Duscher.

7/10

The video is a live demonstration by an expert operator, showing real-time adjustments and troubleshooting. The scientific content is accurate and well-explained, but the informal and spontaneous nature, with some technical glitches, slightly reduces the overall reliability.

Markers derived by PSI from the transcript: the creator did not define chapters.

• 00:00Introduction and overview of the session: acquiring CBED patterns remotely.
• 02:00Opening the column valve and initial camera setup; encountering a bug.
• 04:00Acquiring first diffraction pattern and observing a hole in the sample.
• 06:00Moving to a thicker region of the FIB sample and zooming out.
• 08:00Tilting the sample to align with the zone axis; observing Kikuchi lines.
• 10:00Scanning in a small area to improve pattern clarity; observing four-fold symmetry.
• 12:00Discussion of the HAADF detector and its effect on the diffraction pattern.
• 14:00Adjusting the convergence angle to make the diffraction discs just touch.
• 16:00Detailed observation of excitation errors and their dependence on sample thickness.
• 18:00Attempting to align the beam using aperture shifts and diffraction shift.