Dissection Microscopes

Dissection microscopes have low-magnification lenses with long working distances, which give a good depth of field, but a poor resolution. Nevertheless many specimens are photographed unmounted on dissection microscopes equipped with a 35-mm camera attachment. For general observation, there are no rigid principles. Lighting is a matter of personal preference and depends on the specimen. However, where live specimens are being observed, "cold" light sources (where the lamp is remote and the light transmitted to the specimen by fiber optics) are preferred to lamps integrated into the microscope stand (which generate heat). Most dissection scopes give the opportunity for transillumination (light shining through the specimen) and transparent Sylgard- (see Subheading 2.1.) coated dishes have therefore generally replaced wax as a substrate for pinning out specimens. For photomicrography, translucent agar-ose-filled dishes provide a less rigid support for the specimen, but give a more diffuse background light (see Subheading 2.2.). In terms of camera focusing and choice of film, the same principles apply as for compound microscopes (see Subheading 4.).

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