A photomicrograph is a photograph of something under magnification, taken through a microscope. Since the early days of photography, people have been attempting to produce photographic images of the things they view through microscopes, with varying degrees of success. There are a number of challenges which must be overcome when taking a photomicrograph to produce an image of good quality.
One approach to taking a photomicrograph involves fitting a camera to the eyepiece of a microscope. The specimen is mounted in the microscope, the microscope is adjusted and focused, and then the camera is focused and a photograph is taken. Another technique involves the use of a specialized microscope with a built in camera which can be used to take still or video images of objects on the stage of the microscope.
Getting a good photomicrograph requires a very fine degree of focus, and a camera lens which is capable of focusing under the conditions found with a microscope. Light is also usually a critical issue, as enough light for a clear image is needed without washing out the object on the microscope stage or damaging it with light. The process can get even more complicated when someone needs to take a photomicrograph of something such as a sample which needs to be viewed under blacklight to highlight a stain or another feature.
In addition to photographing with a regular microscope, photographs can also be taken with an electron microscope. Electron photomicrographs can be extremely detailed and rich, showing a high level of magnification and revealing structures which may not be readily visible on a regular microscope. An electron microscope's powers of resolution are much higher than an ordinary light microscope, and this can be clearly illustrated by looking at photomicrographs of the same object viewed under light microscopy and then under electron microscopy.
Many people have seen photomicrographs, even if they aren't aware of it. Biology textbooks usually feature a number of examples, and an image search on any search engine for “photomicrograph” can turn up beautiful, haunting, and astonishing images. Under microscopy, an object as ordinary as a grain of pollen can become extraordinary.
In addition to being used to illustrate science textbooks and get people enthused about science, photomicrographs are also used in pathology, to create images of cells for additional reference, and in fields such as forensic science and general biology, among many other places. Photomicrographs commonly accompany scientific publications which can range from the discovery of a new virus to research about the inner workings of plant cells.
