This tutorial explores how specimen appearance is altered with color changes in both the central and annular filters in a virtual microscope equipped with Rheinberg illumination.

	Interactive Java Tutorial
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To operate the tutorial, use the Filter sliders to change the wavelengths passed by the central and annular filters. The slider on the left controls the annular filter color, which alters oblique illumination of the specimen. The right-hand slider controls central illumination color, the color of the background. The purpose of the tutorial is to allow visitors to explore how filter combinations can be modified to optimize specimen contrast. The stage rotation angle slider is used to rotate the sample in a full 360-degree circle around the optical axis of the microscope.