Practical considerations of objective lenses for application in cell biology.

For nearly a century, examination of biological phenomena on a microscopic level has depended on carefully calibrated optical systems, with the objective lens being regarded as the critical determinant of image quality. In this modern day, a wide variety of high-quality objectives exist, many with highly specialized functions and all requiring at least a certain base level of knowledge on the part of the imager in order to realize their full potential. A good working knowledge of objective construction, proper use, specialized applications, and care goes a long way toward obtaining quality results. Presented here is a practical guide to choosing, using, and maintaining the proper objective for a given biological imaging application.