Document Type

Technical Report

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Algae, bioindicators, data analysis, water quality standards


The focus of this research project was to continue the development of a photographic system which would record living organisms using various forms of light microscopy with correct color and with arrested movement. These demands dictate the use of an electronic flash source with metering and control system located in a position following the passage of the light through the optical train. The system developed uses off-the-shelf components with a modified flashtube holder which positions the tube in the axis of the light beam between the field and iris diaphragm. The light is measured off-the-film so that light from the microscope and flash are combined. The flash is quenched and shutter closed based upon the combined reading. The second phase of the research project concentrated on (1) improving the adaptability of the equipment to various microscopes, (2) testing the system under various lighting conditions, and (3) producing high quality micrographs of selected verified taxa. The micrographs will be incorporated into an existing ecological data base of the algae of Arkansas. Many of the organisms are ubiquitous. Therefore, micrographs are useful for comparison with other sources as well as serving as a verified reference resources of Arkansas taxa.

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