Image intensification techniques for detection of proteins in cultured cells

We describe here the components and uses of two image intensifier systems. The SIT camera system is convenient, relatively inexpensive, readily adaptable to most microscopes, and reliable. It suffers from lack of resolution at high gain levels and the inability to extend its sensitivity by accumulating an image over time. The EMI system is expensive and bulky and requires special adaptation to the microscope and special image recording devices in its output. It has extraordinary sensitivity and resolution, however, and allows experiments to be carried out that are otherwise not possible. Other systems similar to those described here are also commercially available and, in general, have similar advantages and disadvantages. The choice of the proper type of system varies with the particular application. These systems amplify the amount of light in an available image within constraints of gain and resolution and produce a publishable record of what otherwise might not be able to be recorded. These systems cannot improve images that contain too much background nor improve the resolution inherent in the microscopic method employed.