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Autofocus
. Autofocus is activated by clicking the ‘auto’ button on the Focus toolbar. The
uScope Software can also be set to automatically autofocus after moving to one of the preset
settings (A-D on the SVM340 front panel or A-H from the uScope software).
Settings for the autofocus algorithm and preferences are found in the
Autofocus Settings
Window (access via SVM>Autofocus Settings…).
The optimized autofocus settings will depend on the optics module used, camera frame rate,
individual image properties, and magnification. The settings marked
below are those
typically adjusted to optimize autofocus.
Apply Gaussian blur*
(default: on, 1.25 pixels): Blurs image to reduce the effect of image noise on focus
algorithm. May need to be increased for noisier images.
Final passes
(default 1): Sets number of passes to make once focus location is established.
Exploration range*
(default 800): Sets the tolerance for how hard auto focus will try to find a
focus point.
Exploration impatience
(default 0.1): Used in exploration range calculation. When focus is
getting worse, multiplies impatience.
Focus speed
(default 24): Increase if focus motor is stalling during autofocus.
Focus speed bias
(default 2): Bias between focus up and down speed.
Convergence relaxation
(default 0.25): Affects focus convergence.
Pre-emphasis
(default 1.5): Setting for homing in on final position. Increase if the autofocus
final position typically goes past ideal focus position, decrease if autofocus stops short of ideal
focus.
