A small computer system for micrograph analysis

A small computer system is described that makes use of video graphics to interactively analyze electron micrographs. The advent of relatively inexpensive digital frame buffers (digital memory that holds one TV frame) permits an image of at least 512X512 pixel resolution to be displayed and rapidly changed in contrast, brightness, and color. These devices can also perform pan (picture movement), zoom and marking of objects of interest with circles, vectors and alphanumerics. These features have suddenly made it possible to quantitatively analyze micrographs in an efficient and interactive way. A minimal system is described here to implement the application of this equipment to measure molecular weights of individual proteins (or mass per unit length measurements) and to perform several image enhancement processes such as background gradient removal and contouring of molecules. This system is a stand-alone microcomputer with disk, video processor and TV set and is simple enough to permit an untrained user to make a statistical study of his micrographs after only a few minutes of instruction.