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Anamorphic lens squeeze. Values greater than one decrease the effect of the lens distortion in the X direction. Values less than one increase it.
Transverse (or lateral) chromatic aberration. This specifies the magnification factors for the red, green, and blue primaries respectively. When unequal, this can produce a tinge which is most pronounced near the image edges. It will increase color noise, however.
Axial (or longitudinal) chromatic aberration. This specifies the chromatic focal shift for the red, green, and blue primaries respectively. When unequal, this can produce a tinge on bokeh and out of focus objects. It will increase color noise, however.
Natural vignetting. When one, directions off of the primary camera axis will be darkened realistically. Wide-angle perspectives will show this effect more strongly. Setting to zero disables this and intermediate values will blend accordingly.
Optical vignetting. Simulates light blockage due to a hood or other additional lens elements. With depth of field enabled, this creates cat's eye bokeh. However, it also increases image noise.
Shutter direction. Specifies the direction that the shutter sweeps. The default, down, is the most common direction for rolling shutters.
Exposure duration. Zero means an ideal rolling shutter where each line is exposed instantaneously when read. The default, one, is equivalent to a global shutter where all lines are exposed and read at the same time.