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Posted by Mark & Mary Ann Weiss on 06/27/07 07:59
I've started a small site with example footage and stills taken from an HDV
camera, the Sony HVR-V1U. Aside from it's terrible audio, the camera
produces decent images in sunlit environments, but there are a number of
artifacts which are changing in a distracting temporal manner, as the camera
pans across scenes.
I put some examples up here:
http://www.basspig.com/hvrv1u_HDV_artifacts.htm
HDV is really severely compressed and breaks down badly with imager noise,
so in low light situations, the CODEC is overstressed and picture quality
nosedives. This is also true with busy images, like a pan across a grassy
field (the grass shimmers because the imager resolves individual blades of
grass, and the HDV CODEC can't handle all that high frequency detail without
generating spurious color information that shows up temporaly as a
shimmering effect.
I suspect that the color palette of HDV is less than 24 bit, because at
times, the picture shows striated bands of color, like a GIF image when too
many diverse colors are present. Ironically, the noisy imagers in this
camera should 'dither' the image and eliminate the banding, but it does not.
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