Burn-In, Foot-Lamberts, Commercial Volume

No TV!
I want to replace the aging rear-projection TV in my home theater, possibly with a Pioneer Elite PRO-111FD. I will be watching mostly Blu-rays with no broadcast viewing at all. Since most Blu-rays have some sort of letterboxing, will there be a problem with image retention or burn-in? If so, what 50-52 inch LCD do you recommend?

Greg Kalbrunner

I agree that if you only watch letterboxed movies and no HDTV, burn-in could become an issue over time. But most plasmas, including the Pioneers, provide a "screen wipe" function that floods the entire screen with white to prevent burn in. Just activate this function once a week or so and you won't have a problem.

Too Bright!
My retailer recommends obtaining at least 40 foot-lamberts in a home-theater setup to get that "pop" in the picture. However, other sources say the cinema standard is 16fL. Projectors such as those from JVC, Sony, or Optoma do not have the light output to produce 40fL even on a modest 100-inch screen—you need an expensive Runco with a 2000-lumen output to achieve this goal. What is the optimal foot-lambert value to shoot for?

Raghu Pulluru

In my opinion, 40 foot-lamberts is too bright, at least in a dark room. THX recommends 30fL for LCDs and plasmas, again in a dark room. If you have unavoidable room light, it can be brighter.

As for front projectors, 40fL is ridiculous. The cinema standard is indeed 16fL, and that's what I strive for in a home theater as well. Of course, this assumes a completely dark room, which is required for any front-projection system.

Too Loud!
The sound level of TV commercials is outrageous! My normal volume setting is 25, but when commercials come on, I have to lower the level to 3 or 4 (or mute). Are there any TVs or home-theater-in-a-box systems that automatically adjust the sound level to combat this problem?

David Hicks

I know of two systems that do exactly what you want: Audyssey Dynamic Volume and Dolby Volume. Both are OEM systems—that is, they are licensed to manufacturers who integrate them into their products. Many Denon, Integra, and Onkyo AVRs provide Audyssey Dynamic Volume, while the Harmon Kardon AVR 7550HD, Arcam FMJ AVR600, and AudioControl Concert AVR-1 receivers provide Dolby Volume. I know of no HTIBs that provide either one. Toshiba's ZV650 series of LCD TVs will have Dolby Volume, but it's not on the market yet.

If you have a home-theater question, please send it to scott.wilkinson@sorc.com.

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COMMENTS
Scott MacMillan's picture

Just a quick comment on the Plasma burn in; you will experience no burn in if you are watching 1 -3 movies a night, even with letterboxing. The only time you will really notice burn in from letterboxed movies is if you have them running day in/day out; I say this with confidence since I have had plasmas running for hours on end with letterboxing and have never had a case of burn in on any model in the last 4 years. Do not confuse image retention with burn in, they are not the same thing.

Scott's picture

Commenting on the volume settings. Pioneer also has a function in their Elite series known as DialNorm which serves the same function as Audyssey and Dolby Volume. The only problem is that it can not be turned off. So if trying to bitstream any hi-def audio to these receivers from your blu-ray player, the receiver automatically adjusts the volume between the Dolby Digital and TrueHD and DTS-Master Audio. So if trying to hear a difference between the formats, the receiver automatically adjusts the volumes to be about the same. The way of getting around this is to have the blu-ray player internally decode and send it over HDMI or analog outs. But then you won't be able to see your fancy display show you TrueHD or DTS-Master.

Påhl Melin's picture

There is a wide-spread misconception on plasma burn in when it comes to letterboxing. But burn in does not occur in black areas on the screen, at all. Burn in is caused by stressing the phosphor by a bright signal being constant on for a long time. But in the letter box the signal is *off* – there is no stress on the phosphor. Still, there is a possible problem with letterboxing, and it's caused by the aging of the phosphor. A normal plasma screen (or LCD for that matter) looses half of its brightness in maybe 60,000 to 100,000 hours. But the aging in the letter box area is much less (maybe none at all) so the effect will be that the letter box area will become relatively brighter over time when you watch full screen material. How many years it will take until you notice the problem? I don't know, but it will take many years, at the least, if there will be a problem at all. And it's impossible to stop the (marginal) problem by using burn-in prevention like "screen wipe". And LCD has e

Ron W's picture

I couldn't agree with Pahl Melin more. From my experience especially with large screen RP CRT's, the "burn-in" comes from areas of white or high contrast(particularly lines or print) NOT the dark areas such as letterboxing in movies. That is why I could never understand the constant "warnings" in this particular instance. The problem, today, lies with television stations that have many "fixed" bright images on the screen all the time and if you spend a considerable amount of time constantly tuned to this type of channel, that is where the most potential for "permanent" burn-in occurs.

Scott Wilkinson's picture

I'm not saying that burn-in or image retention occurs in the letterbox-bar areas, but rather that after displaying lots of letterboxed or 4:3 material, an outline of the letterbox or 4:3 window can be visible in full-screen images. I agree that this is much less of a problem than many people make it out to be, but I have seen it, and it didn't take years to show up. My mom's plasma TV is a perfect example; she watches mostly 4:3, and that window is visible when she switches to an HD station.This effect is undoubtedly image retention, not burn-in; Scott is correct that they aren't the same thing. Image retention is temporary and can be eliminated by displaying a full-screen moving image or activating the set's screen-wipe function, while burn-in is permanent. What most people call burn-in is actually image retention and thus not a big problem.

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