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View Full Version : An Analogue Artifact Whose Name I Do Not Know!


dbzgundam
17th March 2009, 19:44
Been a while since I posted anything here, but I come asking for some advice (not necessarily a solution, as my boss doesn't seem to have the eyes for this) on a particular analogue artifact.

Here's a sample clip (in its "original" DV form): http://www.yousendit.com/download/UmNJdFdYQVNrWTljR0E9PQ

The following was shot on Betacam SP and digitized to standard NTSC DV, there's no further encoding on the clip. Anyway, if you look to the speaker's left arm, there are stray black lines flickering off of her. I've noticed this for years now (and didn't care, as it seemed to be a shortcoming of analogue), but my coworker was curious, so I figured I'd ask around. It's not rainbowing, dotcrawl, noise (at least the way we usually perceive), or some banding of any kind, so I'm not even sure how I could possibly treat this, be in it AVISynth, or before even capturing the video.

I suspect this is either inevitably analogue's fault, or perhaps the recorder (the camera itself) it dirty in some way. Any advice is appreciated!

communist
17th March 2009, 21:24
Never seen this directly on analog recordings. Only on analog sat-tv - there it was called spikes / fishes.

scharfis_brain
17th March 2009, 21:41
I've seen this artifact so far on analogue sattelite transmissions as well es on bad VHS-Transfers (probably due to dirty or misaligned heads)

SeeMoreDigital
17th March 2009, 22:18
Is the woman standing in-front of a blue/green screen? If-so it could be a chromakey anomoly....

http://i39.tinypic.com/2iadc2h.jpg

dbzgundam
17th March 2009, 22:51
Is the woman standing in-front of a blue/green screen? If-so it could be a chromakey anomoly....

http://i39.tinypic.com/2iadc2h.jpg
No, she's just standing in front of a very brightly lit white background.

2Bdecided
18th March 2009, 10:38
That's just head wear (or dirty heads) - either on the playback machine, or the original recording machine, or both.

Using the machine it was originally recorded on for playback can help. Or try any other machine.

There's a thread about trying to fix the issue digitally here:
http://forum.doom9.org/showthread.php?t=121197

Hope this helps.

Cheers,
David.