These images were taken with electron microscopes. They were originally in black and white, but I colorized them for fun and to highlight various features. Below are "before" and "after" shots.
There are two primary types of electron microscopes - Scanning Electron Microscopes (SEMs) and Transmission Electron Microscopes (TEMs). There are also other types of microscopes and endless varieties of each!
Most of the images on this web site were taken with an SEM, which is generally used to image the surfaces of things. A beam of primary electrons is scanned rasterwise across the surface of a specimen. Those electrons interact with the specimen to kick off other particles. These include secondary electrons, commonly used to form an image, backscattered electrons with energies related to the element that gave them off, X-rays that also contain elemental information, Auger electrons, and photons, all of which contain some information about the specimen. Most of the images on this site were taken in secondary electron detection mode. Where lots of electrons were given off in the direction of the secondary electron detector, the image is bright. Where fewer reached the detector, the image is dark. In this way a black and white image is formed which gives information about the topography of the specimen. In other words, you can see lots of detail on these bugs!
In TEM the electrons are transmitted through a very thin specimen or an ultrathin section of a sample. Where the electrons get through to strike the screen or film the image is bright, and where the electrons are scattered away the image is dark. Sections and thin specimens can be stained in various ways to increase electron scattering and contribute to image contrast. The electrons that are scattered by the specimen also contain elemental information about the specimen, but I am just getting into that and so that is a story for another day!
For more about the electron microscopes I use, visit the Pacific Biomedical Research Center's Biological Electron Microscope Facility at the University of Hawaii.
So how do the black and white images get colored? I use Adobe Photoshop and "paint" the images with a mouse or digital pen and pad. The colors are a product of my imagination, especially the TEMs of cells, which usually have little or no color at all!
I hope you enjoy visiting my little world!
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Copyright © 1996-2000 Tina (Weatherby) Carvalho...MicroAngela
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