Brightfield Observation (Bf); Phase Contrast Observation (Ph); Use Of The Green Filter - Optika Italy B-810 Serie Manuel D'instructions

11.1 Brightfield Observation (BF)
1. Move the condenser slider to the middle position
to insert the empty position. (Fig. 33)
2. Now repeat the steps described in the chapter
"Brightfield observation procedure".
11.2 Phase Contrast Observation (PH)
1. Center the condenser as already described in the
chapter 9.10.
• This condenser does not have a swing-out lens,
so the operation described in step 2 is not needed.
2. Move the condenser slider to the right to insert
the phase ring 10 (Fig. 34) or to the left to insert
the phase ring 40. (Fig. 35)
3. Insert the corresponding objective in to the light
path.
4. Open the aperture diaphragm.
5. Place a specimen on the stage and focus.
6. Remove one eyepiece and insert the centering
telescope. (Fig. 25)
7. Rotate the upper part of the centering telescope
until the two phase rings (one dark and one bright)
visible in the telescope are in focus. (Fig. 25-26)
8. Using the centering screws on the slider ① (Fig.
36), cener the rings as already described in
chapter 10.3.
9. At the end remove the centering telescope,
reinstall the eyepiece and begin observation.
• With 40x and 100x objectives it may be useful
to slightly raise the condenser, to obtain a
better projection of the phase rings. This is
not a defect.
• With the 4X objective, the condenser could
have a dark halo at the periphery of the field
of view. This is not to be considered a defect.
11.3 Use of the green filter
• The green filter is used to increase the contrast
of the image during phase contrast observation.
• Place the filter on the field lens of the microscope
(Fig. 29) and begin the observation.
• For observation in brightfield it is advisable to
remove the filter from the optical path.
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Fig. 34
Fig. 35
Fig. 36
Fig. 36