From 0cd673b5eb2e3e3f7213112d12ed8586c64158f5 Mon Sep 17 00:00:00 2001 From: skoupy_r Date: Fri, 15 Mar 2024 17:26:28 +0100 Subject: [PATCH] Update Calibrations --- Calibrations.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/Calibrations.md b/Calibrations.md index 06ff582..0d03811 100644 --- a/Calibrations.md +++ b/Calibrations.md @@ -1,3 +1,8 @@ +##### Probe semi-angle + +##### Detector camera length +Pixelated STEM detector is located at a different position compared to level of nominal camera length (dedicated STEM detectors in our case). Real camera length to the pixelated detector has to be measured for each available nominal camera length. Otherwise wrong detector cover angle is used in reconstructions. + ##### Scanning step correction Scanning step size is given by magnification and number of scanning points giving together field of view. In reality, original calibration may not be perfectly accurate and own re-calibration may be needed. Scanning step calibration is based on known inter-atomic distance. In our case _SmB6_ in [110] orientation where _Sm_ to _Sm_ distance is 2.92 or 4.13 A respectively. Line of 23 _Sm_ atoms was imaged in 499 pixels, 1 pixel is 22 * 2.92 / 499 = 0.1287 A. Microscope field of view at 30e6 magnification is 7.154 nm here divided into 512 pixels (pixel 0.1397 A). Correction factor between real and nominal pixel size is then 0.1287/0.1397 = 0.9212 = 92.12 %