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Camera Performance and Features
Linea HS Series Camera User's Manual
Camera Performance and
Features
This section is intended to be a progressive introduction to camera features, including explanations
of how to use them effectively.
Synchronizing to Object Motion
Acquiring Images: Triggering the Camera
Related Features:
Several different methods can be used to trigger image acquisition in the camera:
Internal Trigger
The simplest method is to set the
Trigger Mode
feature to “Internal”
. This results in the camera
being triggered by an internal timer, which can be adjusted using the
Acquisition Line Rate
feature.
External Triggers
When the
Trigger Mode
feature is set to
“External”
, the camera triggers come from a different
source selected through the
Trigger Source
feature.
The available sources for the triggers are from pin 5 of the GPIO connector, from the Camera Link
HS frame grabber, or from the rotary encoder feature (using pin 5 and pin 6 of the GPIO
connector).
Use the
Trigger Activation
feature to select the edge that triggers the camera. The options are:
Rising Edge
,
Falling Edge
or
Any Edge
. When using
Any Edge
be careful that the time between
edges does not exceed the maximum line rate of the camera. If the line rate is exceeded one of
those edges will be ignored.
CamExpert can be used to configure the frame grabber for routing the encoder signal from the
frame grabber input to the trigger input of the camera via the Camera Link HS data cable.
Line Rate & Synchronization
A continuous stream of encoder trigger pulses, synchronized to the object motion, establishes the
line rate. The faster the object’s motion
is, the higher the line rate. The camera can accommodate
triggers up to its specified maximum frequency. If the maximum frequency is exceeded, the
camera will continue to output image data at the maximum specified. The result will be that some
trigger pulses will be missed and there will be an associated distortion (compression in the scan
direction) of the image data. When the line rate returns to or below the maximum specified, then
normal imaging will be reestablished.