Adjusting Parafocality 

Adjusting the Microscope for Parafocality


  1. First position the eyepieces to fit the space of your eyes (Interpupillary distance). Make sure the eye cups are up if you do not wear glasses.
  2. Set both eyepieces to zero +/- =0
  3. On low power focus on a specimen. I usually use a business card
  4. Switch to High power and re-focus if necessary.
  5. Adjusting the dioptric settings: Switch back to Low power and without looking into the scope move the eyepieces counterclockwise in the “+” direction as far as possible (+5).
  6. Cover one eye and slowly rotate the visible eyepiece in the “-“ direction (clockwise) until the image comes into focus. Do this with the other eyepiece.
  7. The focus of the image should be constant as you move to higher or lower magnification (parafocal).