Dave Mitchell's DigitalMicrograph™ Scripting Website

Function

Automatically measures resolution test images to obtain a resolution value for SEM, STEM etc.

Version

version:20221021, v2.0

Author

D. R. G. Mitchell

Acknowledgements

Based on the PATE software by Carl Zeiss.

Comments

Resolution test specimens are often small gold particles on a carbon support. These provide high contrast images in HAADF, SE or BSE modes. This software works by identifying high contrast edges in such images and extracting the intensity profile thereof. An erf curve is fitted to the profile and the distance over which the intensity profile changes from 25% to 75% is reported as the resolution. Poor fits are excluded and data can be easily refined to exclude outliers. Measurement is carried out in four directions to evaluate any astimatism which may be present.

Updated in v2.0 to be compatible with GMS 3.x.

System Requirements

Should be compatible with all recent versions of DigitalMicrograph.

Known Issues

This can be used on any kind of image - TEM/STEM/SEM/AFM etc. The only requirement is that the image be high contrast and that the features being measured produce sharp edges - which are smeared due to the shape of the imaging probe. Images must be spatially calibrated for this to work - recalibrate images within DigitalMicrograph if importing SEM or other non-TEM sourced images. Import such images in TIFF or BMP format. Do not use the JPEG formats as these produce compression artefacts. Images with data bars containing text, scale bars etc will interfere with this measurement. Simply create a region of interest over just the region of the image to be evaluated and the data bars will be excluded automatically when the script is run.

Some iteration may be necessary to find an appropriate number of edges and to set up the measurement parameters. A detailed help file is embedded in the script - press the '?' button to write the instructions to the Output/Results window.

Supported

Yes

Included Files

Main script file.

Source Code