Specifications

Operation
Carl Zeiss Transmitted-light darkfield Axiostar plus
3-10 B 40-81 e 12/01
Setting darkfield contrast with dry
darkfield condensers
• If necessary, swivel open the wide-angle
unit, colored disk carrier, polarizer or λ
plate.
• Move condenser carrier down until it makes
contact.
• Place dry darkfield condenser in darkfield
condenser carrier (see section 2).
• Place darkfield condenser carrier in
condenser carrier and center approximately
so that when the condenser carrier moves
the condenser moves into the gap of the
mechanical stage without making contact.
• Move condenser up until it makes contact.
• Place specimen.
• Set lamp brightness to maximum.
• Swivel in objective with a small
magnification (e.g. 5x or 10x) and focus the
specimen with the focusing drive.
• Since you can only see the specimen where
small components illuminate when using
darkfield illumination, set the specimen so
that an even detail distribution can be seen.
This will make the imaging of the luminous
field diaphragm easier to identify.
• Close luminous field diaphragm by turning
luminous field diaphragm ring
counterclockwise until it makes contact.
• Lower the condenser until the edge of the
luminous field diaphragm is displayed
clearly (luminous field diaphragm focus
level). There will be an increasing or
decreasing light ring above or below the
focus level of the luminous field diaphragm
(circular “breathing” of the luminous field
diaphragm depiction).
• Recenter the luminous field diaphragm with
the adjustment screws on the condenser
carrier.
• Swivel in desired objective.
• Reset focus level with Z drive. Focus the
luminous field diaphragm with the
condenser drive. Open the luminous field
diaphragm just above the viewing field
edge.
• Optimize the contrast with the condenser
drive, if necessary.
Additional information:
Darkfield specimens require a considerably
higher level of cleanliness than specimens for
other methods; fingerprints, dirt and dust in
particular brighten the background.