Axioskop 2 plus OPERATIONAxioskop 2 mot plus Illumination and contrasting techniques Carl ZeissB 40-075 e 02/01 3-25• Swing in 10x objective (yellow ring, see p. 1-12)in the nosepiece (3-17/6) and focus on thespecimen via drive (3-17/2).• Close luminous-field diaphragm (3-17/4) until itbecomes visible (even if not in focus) in the fieldof view (3-17/A).• Use drive for height adjustment (3-18/2) tolower condenser until the edge of theluminous-field diaphragm appears in focus(3-17/B).• Use both centering screws (3-18/3) of theuniversal condenser to center the luminous-fielddiaphragm (3-17/C) and then open thediaphragm until its edge just disappears fromthe field of view (3-17/D).• For aperture diaphragm setting (contrast),remove one eyepiece from the tube and lookinto the tube with your naked eye. Use slidingknob (3-17/5) to set the aperture diaphragm toapprox. 2/3 ... 4/5 of the diameter of theobjective exit pupils (3-17/E). In mostapplications, this aperture diaphragm settingprovides optimum contrast at almost idealresolution, and is therefore the bestcompromise for the human eye.• Insert eyepiece in the tube again.☞ Since field size and objective aperture change after every objective change, the setting of theluminous-field diaphragm and the aperture diaphragm must be repeated to obtain optimumresults.For < 10x objectives, the front lens of the condenser must be folded out and the aperturediaphragm fully opened. In the case of such large fields, the luminous-field diaphragm can alsobe used for better contrasting by reducing its opening until it becomes visible in the field ofview.102030405060708090100Fig. 3-17 Microscope settings on theAxioskop 2 plus in transmitted-lightbrightfield
