Green Line across top of DVCAM tapes at DVinfo.net

Ben Gurvich · August 2nd, 2006, 06:34 PM

Hi,

Just wondering if anyone has had a problem where tapes , usually from outide sources have a green line across the top. Its not visible on a Video Monitor, only when capturing to an NLE.

Cheers,
Ben Gurvich

Reese Leysen · June 17th, 2007, 02:13 PM

Bumping this thread up because I have exactly the same problem, anyone have any idea?

Bill Davis · June 17th, 2007, 03:44 PM

I've been using DVCAM for about six years now and have shot literally hundreds of tapes and never seen anything like that.

However, it sounds to me like you're having a tracking problem that's screwing up how the camera writes the first line of the visible raster to tape.

Actually, in technical terms, the green line sounds like it's right at the border between the edge of the VERTICAL INTERVAL part of the overall video signal and the actual picture. The vertical interval is the black bar that used to be exposed when an old analog TV signal would lose vertical hold and the bar would ROLL up the picture. (that doesn't really happen anymore with modern solid-state TV sets so you may never have seen it!)

That vertical interval signal area not only contains signal timing info, it also carries data like Closed Captioning information.

Since most video monitors, particularly consumer ones, have a mask (the bezel) that cover the edges of a typical video picture display , it makes sense that you only see it during capture, since the bezel/mask on the TV otherwise covers it up.

If you want to make sure it never shows up for the audience - even on a computer monitor, projection system, or other "full raster" display - just use a one or two line black mask wipe down from the top of the screen before you make your master tapes and that should make it go away.

August 2nd, 2006, 06:34 PM	#1
Ben Gurvich Major Player Join Date: Dec 2003 Location: Australia Posts: 329	Green Line across top of DVCAM tapes Hi, Just wondering if anyone has had a problem where tapes , usually from outide sources have a green line across the top. Its not visible on a Video Monitor, only when capturing to an NLE. Cheers, Ben Gurvich

June 17th, 2007, 02:13 PM	#2
Reese Leysen Regular Crew Join Date: Feb 2007 Location: Belgium Posts: 114	Bumping this thread up because I have exactly the same problem, anyone have any idea?

June 17th, 2007, 03:44 PM	#3
Bill Davis Trustee Join Date: Jan 2004 Location: Scottsdale, AZ 85260 Posts: 1,538	I've been using DVCAM for about six years now and have shot literally hundreds of tapes and never seen anything like that. However, it sounds to me like you're having a tracking problem that's screwing up how the camera writes the first line of the visible raster to tape. Actually, in technical terms, the green line sounds like it's right at the border between the edge of the VERTICAL INTERVAL part of the overall video signal and the actual picture. The vertical interval is the black bar that used to be exposed when an old analog TV signal would lose vertical hold and the bar would ROLL up the picture. (that doesn't really happen anymore with modern solid-state TV sets so you may never have seen it!) That vertical interval signal area not only contains signal timing info, it also carries data like Closed Captioning information. Since most video monitors, particularly consumer ones, have a mask (the bezel) that cover the edges of a typical video picture display , it makes sense that you only see it during capture, since the bezel/mask on the TV otherwise covers it up. If you want to make sure it never shows up for the audience - even on a computer monitor, projection system, or other "full raster" display - just use a one or two line black mask wipe down from the top of the screen before you make your master tapes and that should make it go away.