OperationAxiostar plus Transmitted-light darkfield Carl ZeissB 40-815 e 12/01 3-93.4.3 Setting transmitted-lightdarkfieldBefore starting:– As described in section 2, the microscope isready for operation and switched onaccording to section 3.1.Settings:• Set KÖHLER illumination in the same way asfor transmitted-light brightfield, e.g. withobjective 10x.• Insert the relevant slider (3-8/3) for darkfield− see table on page 3-8 − into the openingon the condenser until stop.• Open the luminous-field diaphragm (3-8/2).• Increase the brightness setting on thepotentiometer.• If the image center is too bright or too dark,sensitively correct the condenser heightuntil the field of view appearshomogeneously dark or featureshomogeneous brightness distribution.For darkfield setting, it is also possible to usethe slider for phase contrast 3 and thefollowing objectives instead of the slider fordarkfield 0.25/0.9: CP-Achromat, A-Plan andPlan-Neofluar 2.5x – 10x and Achroplan 4x.Darkfield condensers can be placed directly inthe Axiostar plus when you use the darkfieldcondenser carrier. Chapter 2 offers an overviewof applicable types and recommendedobjectives.Darkfield specimens require a considerablyhigher level of cleanliness than specimens forother methods; fingerprints, dirt and dust inparticular brighten the background and reducethe contrast of the object image.1 Focusing drive2 Luminous field diaphragm3 Dark field slider4 Aperture diaphragm lever5 Centering screws for condenser6 Nosepiece7 Binocular tubeFig. 3-8 Setting transmitted-light darkfieldArtisan Scientific - Quality Instrumentation ... Guaranteed | (888) 88-SOURCE | www.artisan-scientific.com
