For the digital processing of microscopical images, mosaicking is a prerequisite if the specimen is larger than the camera field at the necessary magnification. This study investigates the possibilities and limitations of fully automated mosaicking on a desktop computer. Cross-correlation-based frame registration was performed with high reliability if the video frames were edge-enhanced before matched filtering, and also in a reasonable time since the search for matches was restricted to pairs of consecutive frames. An environment for routine mosaicking was developed and implemented in a widely used desktop image-processing program. The software developed during this study has been released to the public domain.