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Tom Phillips Micrographic
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Cross Polarized Light Microscopy   Taking photos through a microscope (photomicrography) is tough enough in a bright field, but when you add polarizing filters you limit the amount of light available to photograph and it gets even tougher. To optimize the results, the microscope must be in correct alignment. Aren't most microscopes aligned properly? John Delly the author of Photography Through the Microscope states, “The necessity for proper illumination cannot be over emphasized. All too often, a $25,000 microscope is reduced to the level of a hand magnifier by improper illumination and alignment.” He further notes that in his examination of university microscopes he finds the majority are not in proper alignment. The simplest and most straight forward method of microscope alignment is known as  the Köhler illumination technique. The Köhler illumination technique was first  introduced in 1893 by August Köhler of the Carl Zeiss corporation as a method of providing the optimum specimen illumination. This technique is recommended by all manufacturers of modern laboratory microscopes because it can produce specimen illumination that is uniformly bright and free from glare, thus allowing the user to realize the microscope's full potential. My method? I simply place a piece of white paper over the field diaphragm lens (where the  light comes out at the base of the microscope) stop down the field diaphragm all the way and adjust the light bulb/lamp housing or what ever is necessary until I  can see the bulb filament clearly CENTERED and CRISP on the paper. Then I open the field diaphragm just enough to fill the image in the eyepiece. After that, all other microscope adjustments such as the condenser diaphragm and focus really seem to fall into place. A complete discussion of the Köhler illumination technique would be too much to handle here but if you are interested, there is a fantastic web site on the subject.
We all want more expensive equipment and lot's of it, that's part of the hobby, but high end equipment is not necessary to achieve professional looking results. The aus Jena Fluoval microscope that I am using is a great microscope but it was found with out a power supply or working bulb. These both proved to be made out of 100% pure unobtainium. Even if I wanted to spend the money, I couldn't find them. All the photos in this cross polarized light gallery were taken on that microscope which is illuminated by a $15 halogen landscape lamp that I bought at the hardware store and mounted into the existing lamp house. I used basic Köhler techniques and a piece of paper to adjust it. If you really want to spend some money, buy at least one good objective.