Appendix B Microscope Parts and Kohler Illumination
TO OBTAIN KOHLER ILLUMINATION
- Place a slide on the stage and focus the object using the low-power objective (10X). Ensure that the condenser is completely raised by turning the condenser focus knob towards the back of the microscope.
- Close the field diagram.
- Using the condenser focus knob, lower the condenser until the edges of the field diaphragm are sharply focused.
- Center the image of the field diaphragm using the condenser centering adjustment screws.
- Open the field diaphragm until its image is at the edge of the field. Then open it slightly more so that the image is just beyond the edge.
Note: There are instances in which alternative microscopic applications may require you to adjust your Kohler. Any adjustment of Kohler means that it is no longer set properly and should be reset once you have completed the task. For example, when performing urinalysis or viewing other unstained samples you may have to lower the condenser to achieve better contrast in the structures being viewed.