Camera Performance and Features
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Note that the best flat field calibration can be achieved by performing it at the mid DN level of the
working range used in the operation. Any flat field error associated with residual non-linearity in
the pixel will be halved as compared to performing a calibration at the peak value of the operating
range. A simple way of performing this is to reduce exposure time to half what is used in the
operation in order to get the mid DN level for flat field calibration. Once complete, return the
exposure time to its original setting.
Those areas of the image where high roll-off is present will show higher noise levels after flat field
calibration due to the higher gain values of the correction coefficients. Flat field calibration can only
compensate for up to an 8:1 variation. If the variation exceeds 8:1 then the line profile after
calibration will include pixels that are below the un-calibrated peak level.
Note:
The Linea ML camera has many different modes of operation. It is strongly
recommended that the camera flat field be calibrated for the intended mode of
operation.
Saving & Rapidly Loading a PRNU Set Only
Loading a complete user set takes approximately 800 ms while loading only the user PRNU
coefficients takes less than 200 ms.
Use the User PRNU Set Selector parameter
to select the set you want to save or load. 17 sets are
available
—
16 user and 1 factory. Loading the Factory Set is a good way to clear the user PRNU.
The
Factory Set
is read-only. Loading the Factory Set is a good way to clear the user PRNU.
Save the current user PRNU coefficients using the
“Save User PRNU Set”
feature. Load the user
PRNU coefficients from the set specified using the
“User PRNU Set Selector” and
the
“Load User
PRNU Set”
command features.
Setting Custom Flat Field Coefficients
Flat Field (PRNU) coefficients can be custom modified and uploaded to the camera. They can also
be downloaded from the camera.
To upload or download coefficients, use File
Access Control Category > Upload / Download File >
Settings
and then select
Miscellaneous > Current PRNU
to download / upload a file.
The file format is described in the document 03-084-20133 Linea ML Binary File Format, which can
be obtained from Teledyne DALSA Technical Support. This document also includes Excel spread
sheet examples.
The PRNU coefficients are used by the camera as soon as they are uploaded. To avoid loss at
power up or while changing row settings, the uploaded coefficients should be saved to one of the
available user sets.
Summary of Contents for ML-FM-16K07A
Page 17: ...Linea ML Multiline Monochrome HDR CMOS Cameras 17 Figure 8 Linea ML FM 16K Camera Mechanical ...
Page 18: ...18 Linea ML Multiline Monochrome HDR CMOS Cameras Figure 9 Linea ML HM 16K Camera Mechanical ...
Page 19: ...Linea ML Multiline Monochrome HDR CMOS Cameras 19 Figure 10 ML HM 08K camera mechanical ...
