Abstract: Methods are described for the control of the brightness in a manner independent of color and for the control of the color temperature in a manner independent of brightness, of the illumination light for a microscope device. An apparatus for carrying out the methods includes, beside a main light source 4, a secondary light source 5 with a color filter 6. Both light sources are electrically connected to a common regulating apparatus 8. By means of stored current values and by means of controllers 9, 10 and/or 19 which are to be operated manually, the light sources 4, 5 are driven using appropriate current values.

Abstract: A method and device for measurement of exposure times in optical devices are disclosed. Specifically, a measuring diaphragm plate and a mask plate are associated with a measurement path and a projection path of the optical device and include a plurality of corresponding measuring diaphragms and masks, respectively. A graticule having markings corresponding to the contours of the measuring diaphragms is provided in the projection path proximate the mask plate and conjugate to an intermediate image plane, and a motor for selectively positioning a measuring diaphragm on the measuring path is synchronized with a motor for positioning a corresponding mask on the projection path, such that a selected measuring diaphragm and its corresponding contour markings are simultaneously imaged at the intermediate image plane.