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OptoFidelity Video Multimeter
– User Manual
The functions of this screen are as follows:
•
Pulse length (ms):
the length of the positive pulse in milliseconds that is
generated at the moment of a detected video frame
•
Pulse delay (ms):
the delay in milliseconds between the video frame detection
and the rising edge of the pulse
•
Min. interval (ms):
the time that Video Multimeter waits before outputting
new pulses when new video frames are detected
•
Sensitivity:
adjusts the sensitivity, meaning how small color changes are
considered as frame changes. For most cases, ‘
Med.
’ (Medium) sensitivity is
adequate.
•
Backlight filter:
controls whether the Video Multimeter’s automatic backlight
compensation is active or not. This feature speeds up the reaction time around
1ms. It is suggested that the display brightness is set to 100% if filter is off.
•
Manual trigger:
pressing this button generates a single pulse (for example,
for testing purposes)
6.3
External trigger usage
The external trigger feature is active when the
Trigger camera on frames
application
page is open. Other applications like Framerate can be used simultaneously.
Typical use case is to measure black/white marker with fiber. Color change indication
at BNC connector can be visualized with oscilloscope. Note that if other than
black/white marker types are measured there is significant delay from frame change
to BNC output signal.
7
Camera viewfinder latency option
The signal path from a digital camera to a display causes always some delay, typically
between 100 and 150 milliseconds. Less latency is always best, but the practical limit
for good user experience for sports/action photography is somewhere around 200
milliseconds.
Video Multimeter
can be used to measure any device camera-to-display signal path
latency. These devices include smartphone cameras, tablets, pocket cameras and
DSLRs. Nothing prevents measurement of true end-to-end latency of IP camera-PC
setup as well.
7.1
Option license activation
The Camera viewfinder latency option is activated by copying a valid license file into
the Video Multimeter’s SD-card. The license file name is ‘viewfinder_latency.ini’, and it
should be copied into folder /frm/license/. The file contents is as follows (an example):
; OptoFidelity Video Multimeter license file
; Device serial number: 5
; Feature name: viewfinder_latency
[License]
salt = 1706318843
