On Fri, 13 Oct 2000 16:58:04 -0600, "Montgomery Ward"
>I have a question or two regarding camcorder picture quality. I've had
>several analog camcorders over the last few years and I always seem to come
>up with the same problem. In some shots, particularly outside and high
>contrast, I get a "halo" effect around some of the objects in the pictures
>when I playback on my tapes.
>I know that in graphics work on the computer these distortions are referred
>to as artifacts and usually show up in compressed image formats such as
>jpeg. I'm stumped as what to do about it in videos.
>Is this caused by the camera, camcorder tape, VHS tape, or what.
>I'm considering buying a Digital Video camcorder. Is the problem prevalent
>there too?
>Any suggestions greatly appreciated.
Enhanced edge effect is used to make video images look
sharper, but over-done, the halos are all too evident.
Start with your TV, viewing a bunch of broadcast material.
If the halo effect shows up consistently on high-contrast
edges, reduce the sharpness setting on the TV. Good VHS VCRs
do not generally exaggerate this effect, but some VHS VCRs
do show it. With digital camcorders, this effect is evident
in most, to varying degrees (Canon XL-1 and GL-1 show
this particularly badly, as do others with sharpness controls
available and set too high). Look at the Mini-DV camcorder
comparison article on my web page (listed under the "I
babble" index), where there are frame-grabs from several
camcorders shot under the same various conditions (check
out the images with the person wearing a dark shirt
against a white wall - you will see various amounts of "halo"...).
The tape used has nothing to do with this.