Considerations When Using Binning - Basler Pioneer User Manual

Standard Features

13.6.1 Considerations When Using Binning

Increased Response to Light
Using binning can greatly increase the camera's response to light. When binning is enabled, ac-
quired images may look overexposed. If this is the case, you can reduce the lens aperture, reduce
the intensity of your illumination, reduce the camera's exposure time setting, or reduce the camera's
gain setting.
Reduced Resolution
Using binning effectively reduces the resolution of the camera's imaging sensor. For example, the
sensor in the piA640-210gm camera normally has a resolution of 648 (H) x 488 (V). If you set this
camera to use horizontal binning by 3 and vertical binning by 3, the effective resolution of the sensor
is reduced to 216 (H) by 162 (V). (Note that the 488 pixel vertical dimension of the sensor was not
evenly divisible by 3, so we rounded down to the nearest whole number.)
Possible Image Distortion
Objects will only appear undistorted in the image if the numers of binned lines and columns are
equal. With all other combinations, the imaged objects will appear distorted. If, for example, vertical
binning by 2 is combined with horizontal binning by 4 the widths of the imaged objects will appear
shrunk by a factor of 2 compared to the heights.
If you want to preserve the aspect ratios of imaged objects when using binning you must use vertical
and horizontal binning where equal numbers of lines and columns are binned, e.g. vertical binning
by 3 combined with horizontal binning by 3.
Binning's Effect on AOI Settings
When you have the camera set to use binning, keep in mind that the settings for your area of interest
(AOI) will refer to the binned lines and columns in the sensor and not to the physical lines in the
sensor as they normally would. Another way to think of this is by using the concept of a "virtual sen-
sor." For example, assume that you are using a piA640-210gm camera set for 3 by 3 binning as
described above. In this case, you would act as if you were actually working with a 216 column by
162 line sensor when setting your AOI parameters. The maximum AOI width would be 216 and the
maximum AOI height would be 162. When you set the X Offset and the Width for the AOI, you will
be setting these values in terms of virtual sensor columns. And when you set the Y Offset and the
Height for the AOI, you will be setting these values in terms of virtual sensor lines.
For more informtion about the area of interest (AOI) feature, see Section 13.5 on page 185
190 Basler pioneer