User`s manual

Image Acquisition Control AW00098504000
68 Basler ace Camera Link
The Trigger Selector (This Only Applies When You Are Using Basler pylon)
If you are using the Basler pylon API to parameterize the camera, the concept of the "trigger
selector" is very important to understand when working with the acquisition start and frame start
triggers. Many of the parameter settings and the commands that apply to the triggers have names
that are not specific to a particular type of trigger, for example, the acquisition start trigger has a
mode setting and The frame start trigger has a mode setting. But in Basler pylon there is a single
parameter, the Trigger Mode parameter, that is used to set the mode for both of these triggers. Also,
the Trigger Software command mentioned earlier can be executed for either the acquisition start
trigger or the frame start trigger. So if you want to set the Trigger Mode or execute a Trigger
Software command for the acquisition start trigger rather than the frame start trigger, how do you
do it? The answer is, by using the Trigger Selector parameter. Whenever you want to work with a
specific type of trigger, your first step is to set the Trigger Selector parameter to the trigger you want
to work with (either the acquisition start trigger or the frame start trigger). At that point, the changes
you make to the Trigger Mode, Trigger Source, etc., will be applied to the selected trigger only.
Exposure Time Control
As mentioned earlier, when a frame start trigger signal is applied to the camera, the camera will
begin to acquire a frame. A critical aspect of frame acquisition is how long the pixels in the camera’s
sensor will be exposed to light during the frame acquisition.
If the camera is set for software frame start triggering, the camera’s Exposure Time parameter will
determine the exposure time for each frame.
If the camera is set for hardware frame start triggering, there are two modes of operation: "timed"
and "trigger width". With the "timed" mode, the Exposure Time parameter will determine the
exposure time for each frame. With the "trigger width" mode, the way that you manipulate the rise
and fall of the hardware signal will determine the exposure time. The "trigger width" mode is
especially useful if you want to change the exposure time from frame to frame.