Zoom Microscopes

Zoom microscopes can greatly enhance the ability of a researcher to record his findings by allowing the alteration of an image size from the microscope to a video monitor. There are three usual ways of doing this. Let's take a brief look.

The first uses optical lenses designed to give a video camera variable magnification. This is the best way to achieve zoom microscopes. It is possible with some optical lenses to add a motor that turns the zoom knob for you so you have an automatic zoom function, but this gets rather expensive. It's usually only done for remote applications.

Techniques for Zoom Microscopes

Another way to get set up zoom microscopes is to alter the plane of the CCD video chip, which is the camera itself, on a vertical plane over a video relay lens. This gives an "imitation" zoom that works fairly well with some video relay lenses. Since video cameras were first added to microscopes, this has been a simple but effective means of getting a variable image size onto a television monitor. You can move a camera vertically over a relay lens with the camera's c-clamp onto the video itself.

The last zoom technique is actually a function of the digital electronics included with some cameras. By depressing the zoom button on the camera, the image is digitally magnified. These systems work satisfactorily up to about 50 percent of the total zoom range available. Beyond that, the digital image starts reflecting the fractal imperfections of the digital enhancement with jagged edges--so you don't have a clear image.