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The condensers of various upright and inverted microscopes. The positions of irises and other components vary depending on the manufacturer and model.A. Field diaphragm adjustment (A). The DM2500 field diaphragm is on the other side of the stand. The Nikon Ti field diaphragm is near the top of the transmitted light pillar, labelled FB. Condenser focus (B). This moves the condenser up and down but doesn't affect the focus of the specimenC. Centring screwsscrews (C). The Leica DM2500 and DMI6000 must be centred using hexagonal screwdrivers or Allen keysD. Iris aperture adjustment (D). The iris aperture on the DMI6000 is adjusted using the AP buttons on the left of the microscope stand
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