NTSC = National Television System Standards, the people who invented the
American TV standard back in the early 50s
Engineers joke that it means Never Twice the Same Color
Color bars is an electronic signal that are placed at the beginning of the
tape so that when the tape is duplicated, image values can be matched. The
audio tone is usually 1000 Hertz sine to match audio levels
Both audio tones and video bars are generated by a generator.
That's good advice to use them, but a small library doesn't seem likely to
have such equipment around, nor that to match the signal. Adding them after
the fact is rather like ready-fire-aim. Beside's if they are duping on
equipment with auto level control, their adjustments would be meaningless
Video Works! Is it working for you?
PO Box 273405 - Houston TX 77277-3405
----- Original Message -----
From: "Tony Greiner/Mary Grant" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Wednesday, October 22, 2003 2:24 PM
Subject: [ARSCLIST] Where to find NTSC Color Bar and sound tones
> I am finishing up an article for "Public Libraries" on basic
> videotape preservation for small public libraries. One of my sources
> says that, when preparing a duplicate, to use a "NTSC color bar" and
> a "sound tone" to calibrate the machines.
> Two questions:
> What does NTSC stand for, and where can people get a color bar?
> Is the "sound tone" something that is generated by the player, or is
> this an outside tone as well. If a small library is dubbing a video,
> it is probably using a household VHS- are there household VHS models
> that have these calibration features?
> Tony Greiner
> Tony Greiner/Mary Grant [log in to unmask]