Practical aspects of Boersch phase contrast electron microscopy of biological specimens

► Various obstacles need to be overcome before Boersch phase plates can be used routinely. ► Technical problems include electrostatic charging, mechanical drift, and image artefacts. ► Contamination of Boersch phase plates is analysed by XPS and AES. ► Low-voltage electron microscopy reduces obliteration of low spatial frequencies. ► Single-sideband contrast and mechanical drift are handled by automatic image processing.