White background on TV... causing harm? at DVinfo.net

Matthew Lewis · July 28th, 2005, 12:00 PM

Not sure if this is the appropriate forum for this question, but i'm putting together a tape of a professor's slide show presentation in my NLE program, and i'm wanting to cut between the video of the professor and the actual powerpoint slides (converted to high-res jpegs). The only problem is that all of the slides are black text or images on a pure white background. Will this brighr of a white cause harm to televisions? I know there are such things as "broadcast safe colors" and i plan to apply that filter to the video track, but is a screen of mostly white going to be a bad thing for a TV?
Thanks,
matt

Glenn Chan · July 28th, 2005, 05:04 PM

No. The white may not display properly.

Overly bright+saturated colors aren't safe for broadcast because of the way NTSC television transmission works. Anything approaching 133IRE (composite values) will cause the transmission equipment to overheat. It may also bleed into the audio signal and cause noise in it. Anything too low will interfere with sync signals.

Kyle Ringin · July 28th, 2005, 05:16 PM

I'd just use a brightness/contrast filter to lower the white (while looking at the histogram). Sounds like an instructional video that probably won't go to broadcast, and I'd think most tv's would handle it ok (ie without damage), but equipment considerations aside, black on bright white is hard on the eyes.

There isn't really anything stopping you applying the broadcast safe filter to the track with the slides as well, but I'd go the brightness/contrast filter first.

Stephen Finton · August 12th, 2005, 11:16 AM

Your editing program may call it something like "NTSC filter".

Enable it and it will cut the brightness levels to fit the signal. It would be more accurate to use this feature than just turning down the brightness.

July 28th, 2005, 12:00 PM	#1
Matthew Lewis New Boot Join Date: Jun 2005 Posts: 19	White background on TV... causing harm? Not sure if this is the appropriate forum for this question, but i'm putting together a tape of a professor's slide show presentation in my NLE program, and i'm wanting to cut between the video of the professor and the actual powerpoint slides (converted to high-res jpegs). The only problem is that all of the slides are black text or images on a pure white background. Will this brighr of a white cause harm to televisions? I know there are such things as "broadcast safe colors" and i plan to apply that filter to the video track, but is a screen of mostly white going to be a bad thing for a TV? Thanks, matt

July 28th, 2005, 05:04 PM	#2
Glenn Chan Inner Circle Join Date: Jun 2003 Location: Toronto, Canada Posts: 4,750	No. The white may not display properly. Overly bright+saturated colors aren't safe for broadcast because of the way NTSC television transmission works. Anything approaching 133IRE (composite values) will cause the transmission equipment to overheat. It may also bleed into the audio signal and cause noise in it. Anything too low will interfere with sync signals.

July 28th, 2005, 05:16 PM	#3
Kyle Ringin Major Player Join Date: Oct 2004 Location: Melbourne, Australia Posts: 241	I'd just use a brightness/contrast filter to lower the white (while looking at the histogram). Sounds like an instructional video that probably won't go to broadcast, and I'd think most tv's would handle it ok (ie without damage), but equipment considerations aside, black on bright white is hard on the eyes. There isn't really anything stopping you applying the broadcast safe filter to the track with the slides as well, but I'd go the brightness/contrast filter first.

August 12th, 2005, 11:16 AM	#4
Stephen Finton Major Player Join Date: Jun 2005 Location: Houston, TX Posts: 344	Your editing program may call it something like "NTSC filter". Enable it and it will cut the brightness levels to fit the signal. It would be more accurate to use this feature than just turning down the brightness.