Videomicroscopy in the study of protoplasmic streaming and cell movement

Abstract

Various types of cell motility have been observed and analyzed with techniques of increasing sensitivity and sophistication. Photokymography, cinemicrography and laser-Doppler spectroscopy have all made important contributions to our knowledge of cytoplasmic streaming and cell movement. Now videomicroscopy is finding applications in recording and analyzing two different kinds of images. Video intensification microscopy by image intensifiers and silicon intensified target (SIT) video cameras is used to intensify images too dim to be viewed by eye or photographed. On the other hand, video enhanced microscopy uses a less sensitive chalnicon or other vidicon camera with adjustable amplification and offset to enhance the contrast and improve the resolution of microscopes that employ instrumental compensators. Both of these videotechniques have greatly extended the usefulness of the optical microscope: image intensification to brighten dim images and video enhancement to improve the contrast and resolution so that even “submicroscopic” structures and events can be recorded. These video techniques can both be further extended by a frame memory, with which images can be further enhanced by computer processing. Still to be developed, however, are appropriate methods for automatic tracking of particle motions.