Rainbow effect « Videomaker Community Forums

rbest
Member

I have a JVC S-Video VCR without flying erase heads. When I edit my camcorder videos onto a VHS tape, I get a rainbow effect. Previously, this effect lasted a short time at the edit spot. Now the rainbow effect is remaining for the length of the edit (i.e. minutes). Why the change? What can I do about it?
Ray

Posted 8 years ago #
exceldent
Member

I also have the same problem. It starts from pause or from a stop to record and is a vertical rainbow type that move across the screen and then down. I have not been able to figure out why it does it though.
Good Luck

Posted 8 years ago #
nobody
Member

What you're experiencing is a syncronization problem.
You're laying a new signal down over an older signal and without anything to get the timing correct between the two signals, you're seeing the visible results.

Think of it this way. Video runs at 30 frames (60 fields) per second. If the original tape is at frame 15 and you "crash edit" another signal on top of it such that THAT signal is at frame 05, you're going to have a problem because the timing signal (black burst) of the first signal arrives at a time different from the black burst of the second tape.

Even if you're just "cutting in" a new signal on top of the old, the distance between the erase head and the signal head on your recorder will likely guarantee a period of time when you're signals will be unmatched and you get the rainbow "lost sync" effect.

The "flying erase head" was developed specifically to fix this problem.

"pre roll" on older linear editing systems was designed specifically to give decks time to "line up" their signals prior to edits.

Hope that makes things easier to understand.

Posted 8 years ago #
exceldent
Member

Thanks

That does help. Now I know why two of my vcr's does it and not the other. The one is the next model up and it has a flying erase head.
Can I correct this problem by starting the record from the end of where I have blacked out the first ten seconds of tape? I have just blacked it out and then rewinded it back a few seconds, so that there was not a break in the video.

Thanks Again

Good Luck

Posted 8 years ago #
rbest
Member

Thank you so much. Maybe you can help me with another problem. I have a Samsung 5000W Worldwide VCR (multi-system)which converts NTSC signals to other signals such as PAL. When I try to convert my NTSC camcorder tapes to PAL, I get a light and dark picture appearing plus a reddish hue at times. I tested my Samsung 5000W last night by having an NTSC signal from my antenna go directly into the Samsung and the picture was fine. In other words, it is only doing it with camcorder videos.
Any suggestions? Samsung has been no help. I bought the Samsung specifically for converting to PAL.
Ray BESt

Posted 8 years ago #