The Piranha XL XDR Camera
•
27
during evaluation is not critical and can be internal or externally triggered as long as its period
does not violate the above rule.
Note that when adjusting the exposure time, a momentary loss of LVAL will occur. This will also
happen when changing user sets that include exposure time. In addition, for each exposure time
used an associated FPN and PRNU calibration should be performed and the results stored in a user
set for recovery when the exposure time is selected.
Please note that it is important that customers using the PX-HM-16K12X-00-R model camera run
the FPN and PRNU correction at a line rate above 14 kHz. Failing to do so may result in an
unsatisfactory calibration that will result in an image with vertical streaking.
Measuring Exposure Time
See the section Camera Control Category in Appendix A for GenICam features associated with this
section and how to use them.
Relevant Feature: Measured Exposure Time, Refresh Measured Exposure Time
The camera has the means to measure the exposure time that is currently being internally
generated. This is not a continuous reading but a one-time measurement that needs to be initiated
by the user through issuing a
Refresh Measured Exposure Time
command.
Adjusting Responsivity
See the section Camera Control Category in Appendix A for GenICam features associated with this
section and how to use them.
Relevant Features: Row Selector, Gain Selector, Gain
It is desirable for camera performance to always use the maximum exposure time possible based
on the maximum line rate of the inspection system and any margin that may be required to
accommodate illumination degradation. However, it will be necessary to adjust the responsivity to
achieve the desired output from the camera. The camera has a row selector feature and a gain
feature that can be used to make the necessary adjustment to the responsivity.
Two row selections are available: 8 rows and 12 rows.
•
8 rows offer the highest responsivity at the highest line rate. It is optimized for light starved
inspection systems where low contrast defects must be extracted from dark images and
where the dark noise level needs to be minimized (i.e. minimizes Noise Equivalent
Exposure).
•
12 rows are useful for light starved inspection systems but at a maximum line rate less than
8 rows. This may be useful for lower performance or cost sensitive systems where less
intense, lower cost, illumination is used.
A single gain adjustment is used for any of the row configurations. Gain can be adjusted from
0.65x to 10x (Extended Gain Range Enabled), depending on the number of rows selected. Using
row selection and gain adjustment the camera’s responsivity can be changed by a factor of 15x—
from lowest to highest responsivity performance.
When evaluating responsivity, it is best to start with eight rows and then move to twelve rows if
the resulting responsivity does not meet your application’s requirements.
