Nikon D300 User Manual page 627

image. They are mostly immune to the effects we are about to
discuss.
Here is a list of the effects that can be experienced in extreme
circumstances when using a CMOS sensor's rolling shutter:
▪ Skew – The image leans in one direction or another as
the camera or subject moves. This is often seen at the
edges of buildings and other static objects.
▪ Wobble – This effect is harder to describe. The whole
image wobbles in a strange way. It looks like the top of
the image is out of sync with the middle and bottom of
the image. Since video is a moving picture, the whole
video can wobble back and forth in a very unnatural and
dizzying way.
▪ Partial Exposure – If another camera's flash goes off
during the shot, the burst of light may only be present for
some of the rows of pixels in a particular frame. The top
part of the frame may be brightly lit by the flash, while
the bottom part appears dark. The partial exposure
appears as a bright band in one or a few frames,
depending on how long the brighter light lasts. Some
older forms of fluorescent light have slow ballasts and
can cause the video to have a series of moving bands as
the light flickers. Our eyes can't see it, but the fast video
captures it well. If you are shooting images of an
ambulance with its light flashing, it too can cause
banding. Anything that has intense bursts of light for
short periods may cause partially exposed bands to
appear in the video.
To understand skew and wobble better, let's compare our
camera to a desktop scanner. It works in a similar way. If you
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