DMI4000 and DMI6000 controls (LMCB Leica confocal microscopes)
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The buttons on the stand change a number of settings including the illumination modes (fluorescence, bright-field, etc), aperture sizes and lamp brightness. Some of the buttons are configurable but the main buttons on the front and left of the stand are fixed in their function.
Front control panel
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Buttons 1 and 2 switch the light path to and from the eyepieces and the side port respectively. The position If you don't see any light down the eyepieces then look for the eye icon