It is proposed to test, refine, and improve the design of a stand-alone automatic metaphase finding system that has been constructed with NIH (NIGMS) support over the last two years. The system employs a solid state linear array as an image sensor with an electronic stage driven by fractionally-stepped stepper motors. The entire system is controlled by a NOVA-3 minicomputer with a micro-processor for stage control and a combination of hard-wired logic and minicomputer software to select and "remember" the locations of usable metaphases. It is proposed to test the basic instrument first, both in-house and in the field as well as to develop further three aspects: the high performace digital stage, automatic focusing and use of the microscope as an image digitizer. Both functions are to operate at high power or resolution (at N.A. 1.4 oil immersion resolution). The project involves cooperation of three laboratories; the Tufts Image Analysis Laboratory, the C.S. Draper Laboratory Inc, and the Eunice Kennedy Shriver Center Cytogenetics Laboratory. At the Eunice Kennedy Shriver Center the application will be largely in aminiocentesis work, an activity of growing importance for which automated metaphase finding is particularly important to be able to cope with the growing work load.