User Guide

490 Series Microscope
AmScope Proprietary Page 20 of 64
2.17 Using a Dry Darkfield Condenser Lens (Optional Accessory)
2.17.1 Using the Dry Darkfield Condenser
1. The first step is centering the condenser. Move the 10X objective lens into the
light path.
2. Remove an eyepiece and look through
the empty eye tube, to see the
condenser’s image directly.
3. Use the condenser lens adjustment
knob to adjust the height of the
condenser until the opaque disc is
slightly smaller than the entire image
circle, leaving a ring of light.
4. Turn the condenser’s centering screws
to move the dark spot to the center.
5. Replace the eyepieces.
6. Raise the condenser to the top of its
range, just short of the slide on the
stage. The is the optimal position for
darkfield viewing, but can be adjusted
later, if necessary.
7. Place a slide on the stage and focus. A
djust
the height of the stage up or down slightly
for optimal viewing, but the condenser lens
should be relatively close to the slide.
8. If you are using a variable numerical
aperture objective lens, adjust the ring
at the bottom to fine tune the darkfield.