Basler Pioneer User Manual page 57

Brightness:
Among the factors determining the brightness of an image are the intensity of the illumination, the
setting of the lens aperture, and the settings for black level, exposure time, and gain.
We recommend that you choose bright illumination if possible, but avoid excessive intensity.
This will prevent you from needing to operate the camera using extreme camera settings. A
bright but not excessively bright illumination is of central importance to achieving good image
quality.
In images acquired from CCD sensors, excessive brightness will cause artifacts such as smear
(white stripes in the image) and blooming (local over-saturation that destroys contrast). You
can decrease the proneness for smear and blooming by choosing a diffuse and less intense
illumination.
If illumination of sufficient brightness is not available, you can select a lens that is optimized for
light utilization.
Opening the lens aperture will allow more light to reach the camera's sensor and will therefore
increase the brightness of the image.
Note that opening the lens aperture also increases the effects of optical aberrations. This
causes image distortions and the intensity of light decreases towards the edges of the sensor
(vignetting). In addition, the depth of focus decreases.
You can change the brightness of the image by changing the camera's black level setting.
Normally, you should increase the black level setting only as far as is necessary to make detail
visible in the darkest portions of an image. (This is equivalent to avoiding the clipping of the low
gray values of noise.)
Note that high brightness settings will prevent high contrast. We recommend not using bright-
ness settings above 64 when the camera is set for any output format that is greater than 8 bits
per pixel.
You can increase the brightness of the image by increasing the camera's exposure time
setting. With this method, brightness is increased by increasing the amount of photons
collected for pixel readout.
Note that increasing the exposure time setting may decrease the acquisition frame rate. If you
are acquiring images of moving objects, increasing the exposure time setting may increase mo-
tion blur.
Increasing the gain will also increase image brightness.
Note that unless your application requires extreme contrast, you should make sure that detail
remains visible in the brightest portions of the image when increasing gain. Note also that noise
is increased by increasing gain.
Basler pioneer
Software and Hardware Installation
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