Friday
Jun112010
Jun 11 Podcast #429: TV Specs and Settings - Are they for real?
Category: Podcast
Podcast 
There is a great article at Maximim PC by Dr. Raymond Soneira called "Display Myths Shattered: How Monitor & HDTV Companies Cook Their Specs." We're going to distill it down to a few soundbites and add a little bit of HT Guys color commentary along the way. But if you find the information interesting or useful, we would encourage you to read the full article.
Listen to the show
Today's Show:
News:
- Blu-ray Rentals Likely $1.50 a Night at Redbox Kiosks
- Is HD video in iPhone 4 a Flip Video killer?
- DirecTV software update locks up HD DVRs nationwide -- Update: Fixed
- WD TV Live Plus HD media hub adds Netflix (Pre-order now)
Other:
- Best 3D TV Screen Size and Viewing Distance
- Famous paintings in 3D
- Hear about Ara harmonizing with Minnie in High School
- Is 3D Projection Viable in Great Rooms?
TV Specs and Settings - Are they for real?
There is a great article at Maximim PC by Dr. Raymond Soneira called "Display Myths Shattered: How Monitor & HDTV Companies Cook Their Specs." We're going to distill it down to a few soundbites and add a little bit of HT Guys color commentary along the way. But if you find the information interesting or useful, we would encourage you to read the full article.
Background on TV display settings
Most of you probably already knew that the four main display settings on your HDTV: brightness, contrast, tint, and sharpness, originated with the analog NTSC color TVs of yesteryear, dating back to the 1950's. Most of those settings had specific meanings back then, and for the most part, they don't apply anymore. Back then
Brightness was really an adjustment of the bias of the unit. Bias is an adjustment of how many electrons are hitting the phosphors of the screen. It's a negative offset, so zero bias is full brightness and adjusting the bias will eventually result in no phosphors hitting the screen or total blackness. Contrast controlled a gain factor applied to the color signals shot at the screen, adjusting the overall luminance of the picture. So, in essence, contrast was a brightness adjustment as well.
The other two are very technical, so in Dr. Soneira's words (because we couldn't find better ones of our own): "tint controlled the phase of the color subcarrier, and sharpness performed analog high-frequency peaking to compensate for the limited video bandwidth of the old vacuum tube amplifiers." But ultimately, the bottom line is that none of these controls are necessary for or relevant to the digital signals and televisions we use today.
Settings to Avoid
Almost all of the settings you see listed as "special" technologies on the brochure or the side of the TV box should be turned off immediately. In most cases, it's difficult to determine what those settings actually do. And in many cases they actually decrease picture quality. These settings come by dozens of different names and acronyms, many of which are listed in the article. A few that stood out to us were: Dynamic Contrast, Black Level, Gamma, White Balance, Digital NR, DNIe, Detail Enhancer, Edge Enhancer, and Film Mode.
Contrast Ratio
Contrast ratio, or the ratio of brightness between full white and full black on screen can be a very revealing number. Since most sets can go full white, it really tells you how black a set can get. Keep in mind that really good contrast ratios only matter if you're watching very dark content, like you see in some movies. Most TV viewing never gets into the full black range. Contrast ratio can also be canceled out by the ambient light in the room. No matter how dark the picture gets, it can always be washed out if you can't control the light that doesn't come from the screen.
Possibly the worst misuse of a spec is the so-called dynamic contrast ratio. We have talked about this on the show before. It is a measurement of the ratio of white when the full screen is white to black when the full screen is black. Many televisions can actually reduce or turn off the light source entirely if the screen goes full black, producing an incredibly high ratio. The problem, however, is that the sets cannot do this if they're actually displaying a picture, so you never see anything that dark and the spec is completely useless. What's worse is that many manufacturers are leaving the word "dynamic" off the spec sheet, claiming contrast ratios in the millions. That just isn't accurate.
Response Times
This was a huge eye opener when we first read about it a while ago. It turns out that LCD response times, a spec we always thought was very important, is somewhat meaningless these days. First of all, it would take about a 16ms refresh rate to support 60 fps video. Most, if not all, LCD TVs on the market today are significantly below that threshold. Secondly, in Dr. Soneira's test, the actual measured response time was significantly higher than the published spec. An 8ms SONY LCD had a measured response time of about 65ms, and it was the best performer in the group.
Another equally useless spec that is somewhat related is refresh rate. In an independent test, many viewers were able to see improvements (reduction in) blur on 120Hz televisions over 60Hz sets if they were shown a still image moving quickly across the screen. The same people saw no different when watching actual video content. Since what we watch on TV is very rarely a still image moving quickly across the screen, it stands to reason that there is little if any benefit for normal use, of a 120Hz TV over a 60Hz model. Of course the 120Hz sets tend to be newer, with newer electronics, so it's entirely possible that they have better picture quality - but not due to the refresh rate alone.
Color Gamut
The article goes on to discuss color gamut and how manufacturers reaching to give you a "wider" color gamut are just playing specmanship with you. This also applies to Sharp and their new quattron or quad pixel technology. According to the article, you won't get any benefit from that extra yellow in the color array. The content you're watching is balanced for the RGB sets most people own, which already include yellow.
The article was very informative and gave us some really good food for thought. Our main takeaway was that your eyes are all that matters when it comes to TV picture quality. Regardless of what specs are published, what you see on screen is what counts. Find a TV that works for you, and buy it. So what if someone else has a higher dynamic contrast ratio, faster response time or a wider color gamut. Odds are, nobody can tell the difference anyways.
Reader Comments (5)
Ara and Braden. On today's podcast you discussed the multipurpose room with a flat screen and projector. I wanted to share my experiences with you. My room started out 10 years ago with a 61" rear projection HDTV and surround system. The TV died almost 4 years ago and I went with a 106" screen and projector. Big upgrade for movies and lots of fun. With my wife's help we got almost 100% light control and could use the projector day or night.
I found I missed having the ability to pop down and watch for a brief time since I was unwilling to fire the projector up for viewing less than 2 hours or so. I also found during the day that I did not like sitting in a completely dark room. The current configuration retains the 106" screen but it is now in pull down form and I have added a 50" plasma for casual and daytime viewing and use the projector for movies and longer term night TV viewing and some sports. Using a 4 by 2 monoprice matrix switch has made the conversion a breeze. It also allows use of the computer for games, video streaming or internet sessions on either screen. So far I am very happy to have this flexibility.
Here is a link to an article on the space when it had the fixed 106" screen configuration. It looks much the same now when the 106 screen is pulled down. Other wise you see the 50" plasma at the center of the screen. Link: http://www.electronichouse.com/article/diyer_swears_by_1972_speakers/C154&cid=1114810268&ei=BesHRuOeA5LQqQOt_-HPAg
You recommend if someone is installing Ethernet cable that they use category 6. Given the difficulty of changing wiring, wouldn't it make more sense to spend a little extra to future-proof by putting in category 6a or 7 instead? The cost of the better cable would be swamped by the money and effort to upgrade later, and these cables can be backward compatible with category 5 & 6.
Actually I am not too sure it is worth going for anything over Cat 5e honestly. It will not be too long before you only see fiber optics in homes (see Intel Light Peak technology) or ultra high speed directional wireless (WiGig see http://www.networkworld.com/community/blog/video-wigig-and-60ghz-explained?source=NWWNLE_nlt_daily_am_2010-07-07 for a excellent video explainantion). Most basic computing doesn't need really high speeds until you get into multiple HD video feeds to various locations in your house, and you are going to need an even better pipeline than Cat 6, 6a, or 7. I run single feeds of my Blurays from my HTPC across the house with no stuttering over a Cat5e Gigabit network. I say stick to Cat 5e for now and when you want to upgrade go for Light Peak or WiGig.
Looks like the link for this show is broken... ;(
Great stuff guys - very interesting!