Camera Colors bars, what do they do? at DVinfo.net

Brendan Sundry · March 9th, 2006, 10:35 PM

Just wondering if the bars in a camera are for the editor to align his signal to?

Shane Ross · March 10th, 2006, 12:41 AM

And for setting up machines when you dub them.

Although I find them rather useless in editing. The Black and White levels are always off, and the color as well. I always scan thru a tape and look for the darks and lights to set my levels too, and adjust the color to what pleases my eye.

But I think they are supposed to be for us in theory, just not in practice.

Greg Drusjack · March 10th, 2006, 10:55 AM

Are there Pantone cards that we should use to compare to our color bars or are we supposed to have a photographic mind and very trained eyes to determine just how "out" the colors are.

I guess simply is where is the standard to compare the color bars to? I was a telecommunications student in high school 20 years ago with our own small TV Studio full of donated equipment. We used to use the color bars then to adjust all our monitors, I just can't recall the specifics after all these years (I followed a different path and just now getting back into it).

Greg

Peter Costello · March 10th, 2006, 11:08 AM

I use the bars to set up my field monitors and to make sure my viewfinder (diopter) is in focus.

Steve House · March 10th, 2006, 11:34 AM

Quote:

Originally Posted by Peter Costello

I use the bars to set up my field monitors and to make sure my viewfinder (diopter) is in focus.

Exactly - with the monitors setup using the bars, one can then visually adjust the lighting and the camera colour temperature and levels and see what those adjustments are actually doing to the signal. Otherwise you'd be in the position of not being able to say that green tint you see on the image displayed in the monitor on set was due to the monitor setup being off or to the colour temperature setting in the camera being off

Glenn Chan · March 10th, 2006, 03:52 PM

1- They are used to align the levels in a signal chain... like how 1khz tone is used for audio.

To calibrate monitors:
http://www.videouniversity.com/tvbars2.htm

Another use of color bars is in conjuction with a waveform monitor and vectorscope. You can align decks/VTRs this way.
Tektronix has some great information about this on their website.

2- There are no Pantone cards to match the color bars to as far as I know. However, some companies make something like that... they are physical test charts like Chromadumonde.

http://www.dsclabs.com/chromadumonde.htm

You can 'paint' a camera (tweak its settings) until the colors on the chart line up in a vectorscope. Typically, only the higher end cameras have the settings that allow this.

March 9th, 2006, 10:35 PM	#1
Brendan Sundry Regular Crew Join Date: May 2004 Location: Australia Posts: 112	Camera Colors bars, what do they do? Just wondering if the bars in a camera are for the editor to align his signal to?

March 10th, 2006, 10:55 AM	#3
Greg Drusjack New Boot Join Date: Feb 2006 Location: Cliffwood Beach, New Jersey Posts: 5	In camera use of color bars Are there Pantone cards that we should use to compare to our color bars or are we supposed to have a photographic mind and very trained eyes to determine just how "out" the colors are. I guess simply is where is the standard to compare the color bars to? I was a telecommunications student in high school 20 years ago with our own small TV Studio full of donated equipment. We used to use the color bars then to adjust all our monitors, I just can't recall the specifics after all these years (I followed a different path and just now getting back into it). Greg

March 10th, 2006, 11:08 AM	#4
Peter Costello Regular Crew Join Date: Dec 2005 Location: Phoenix, AZ Posts: 29	bars I use the bars to set up my field monitors and to make sure my viewfinder (diopter) is in focus.

March 10th, 2006, 12:41 AM	#2
Shane Ross Major Player Join Date: Apr 2004 Location: Los Angeles, USA Posts: 539	And for setting up machines when you dub them. Although I find them rather useless in editing. The Black and White levels are always off, and the color as well. I always scan thru a tape and look for the darks and lights to set my levels too, and adjust the color to what pleases my eye. But I think they are supposed to be for us in theory, just not in practice.

March 10th, 2006, 03:52 PM	#6
Glenn Chan Inner Circle Join Date: Jun 2003 Location: Toronto, Canada Posts: 4,750	1- They are used to align the levels in a signal chain... like how 1khz tone is used for audio. To calibrate monitors: http://www.videouniversity.com/tvbars2.htm Another use of color bars is in conjuction with a waveform monitor and vectorscope. You can align decks/VTRs this way. Tektronix has some great information about this on their website. 2- There are no Pantone cards to match the color bars to as far as I know. However, some companies make something like that... they are physical test charts like Chromadumonde. http://www.dsclabs.com/chromadumonde.htm You can 'paint' a camera (tweak its settings) until the colors on the chart line up in a vectorscope. Typically, only the higher end cameras have the settings that allow this.