STOP-DOWN EXPOSURE MEASUREMENT
Although the lens has a built-in ringlight for shooting, you can take pictures without it. In this case, use the stop-down method for exposure measurement. When focused or set to a particular reproduction ratio, the Medical-Nikkor is also automatically set to a particular aperture, which can be read off the focusing ring. Then, to get the correct exposure, you must depress the camera's depth-of-field preview button to stop the lens down to the taking aperture prior to using the camera on Automatic or before adjusting the shutter speed manually. (For details about stop-down exposure measurement, refer to your camera's instruction manual.)
Note : If the automatically or manually selected shutter speed is below approx. 1/125 sec., the use of a tripod to support the cam- era/lens assembly is recommended . Otherwise, the photograph will come out blurred because of camera shake.
