Raise /lower the condenser apparatus by turning
the small black knob (3c
- on the left back
side of the condenser below the stage) until the circumference of the light image is "sharp and
well defined as a hexagon shape."
* Note:
During this process, the particular condenser ring optics can be selected to match the
type of imaging desired:
turn
the condenser (turret) control ring (3d)
to:
HDIC
for brightfield
work;
DIC
for differential interference contrast work. For Phase Contrast work, use no “
1
” for
10X, no “
2
” for 20X and 40X and no “
3
” for 63X objective.
**Note:
it might not be necessary to adjust/focus the condenser for different objective lenses
(magnifications). For example, if condenser is focused for 20x, that could be "acceptable" for
10x and 40x (air objectives); focus for 63x could be "acceptable" for 100x (oil objectives), but
NOT for the 10, 20, and 40x air. Minor re-centering with the condenser centering screws can be
performed:
the light is best centered
when the spot is opened up with the field diaphragm ring
to
about 80- 90% full field illumination
, and the light circumference is "concentric" with the
edge of the field boundary.
***Note
: the silver ring on the condenser opens (clockwise) and closes (counter-clockwise) a
diaphragm for more or less light, respectively — lesser light might give best image (totally
counter-clockwise), however, adjust as necessary for the conditions.
Before
After
Sharp edge
DIC
Brightfield
Phase 1
Phase 3
