Basler GigE VISION CAMERAS User Manual

Acquisition Control AW00118303000
118 Basler racer GigE
Line Acquisition While Obeying Timing Limits
When strictly obeying the following timing limits you can avoid overtriggering in "overlapped mode"
and "non-overlapped mode" without having to monitor the camera’s acquisition status (see also
Fig. 42 and Fig. 43 below). You must ensure that the following four conditions are fulfilled at the
same time:
 Condition one: The exposure time E is 2µs.
This is the minimum allowed exposure time also given in Section 8.2.5 on page 92.
 Condition two: Period F is C
1
(for C
1
values, see Section 8.5 on page 134); period F follows
immediately after the exposure.
The constant C
1
expresses the duration of exposure overhead. Exposure is not possible during
this period. Its default value equals 5.4 µs. However, when the parameter limit is removed from
the Exposure Overhead parameter (see Section 8.3 on page 110), C
1
equals 3.4 µs.
Accordingly, F must be
5.4 µs in the general case, and  3.4 µs when the parameter limit is
removed from the Exposure Overhead parameter.
 Condition three: ExLSTrig Signal Period  Minimum allowed line period.
 Condition four: Make sure the ExposureOverlapTimeMax parameter value is set to the
appropriate value:
appropriate ExposureOverlapTimeMax parameter value =
= minimum allowed line period - duration of exposure overhead (i.e. C
1
,
i.e. minimum F value).
Note: The maximum allowed exposure time E that is compatible with the maximum line rate is
equal to the appropriate ExposureOverlapTimeMax parameter value.
It follows that
 if you increase the ExposureOverlapTimeMax parameter value above its appropriate value
while maintaining the trigger signal period, the minimum value for the duration of the
exposure overhead would be ignored and trigger signals can be considered overtriggers
when in fact they are not.
 if you decrease the ExposureOverlapTimeMax parameter value below its appropriate value
you would have to increase the duration of the exposure overhead and thereby increase the
line rate.
When you want to operate the camera at the maximum allowed line rate and
have set the ExposureOverlapTimeMax parameter value to the appropriate
value (see above) you can vary the exposure time E within a range of values
between 2 µs and the applicable maximum allowed exposure time E (see
condition four).

Basler GigE VISION CAMERAS Specifications

General

Brand	Basler
Model	GigE VISION CAMERAS
Category	Digital Camera
Language	English