Rotate the Left Knob until the Meter reads 5-6 . Adjust the illumination as necessary . You will need greater illumination for high magnifications. Use bright illumination to focus on the specimen. Reduce the illumination to 6 to take a picture.
Short exposures are unreliable.
Thus, the light must be reduced to get a good photo. If you rotate the small central knob which sticks out, the reading will change by 3 DIN numbers which corresponds with corresponding changes in the ASA rating. Check to see that you have the correct film sensitivity selected. It will stay ON when the roll is finished.