16:9 Aspect Ratio and Black Bars

july 21, 2004

I was standing in line today at MicroCenter waiting to pay for a few zip-ties and some cable management loops when a guy stepped in line behind me and tried to speak "authoritatively" about his new LCD television. He boldly exclaimed to his friend waiting in line with him, "See," pointing at a small LCD showing Finding Nemo, "I don't know why I bought a 16:9 widescreen LCD! I still get those black bars when I watch movies. Why did I buy a 16:9 when I still get the black bars?" He continued on that same road of ranting while I stood in line trying to tolerate his inadequate knowledge of movies and movie aspect ratios. "Idiot!" I wanted to exclaim, "If you knew anything about aspect ratios, then you'd keep your mouth shut instead of speaking like a knucklehead." Instead of telling him to Google movie aspect ratios, I finished paying and left. But, for those who are interested, here is why 16:9 still shows black bars at the top and the bottom. Standard definition TV is presented 4:3 and in the old days when TV started to become popular the filmmakers had to find something to make movies different than TV in order to pull in more viewers who were not heading to theaters because of TV. So the studios decided to go with a wider format than TV. The two wider ratios were 2.35:1 and 1.85:1. This definitely made the movies much better as they presented more picture on the sides of the movies -- letting filmmakers do more dramatic framing of scenes also (it's hard to get two heads in a frame with 4:3 almost square ratio). Because of the difference in aspect ratios, when movies are transfered for TV viewing the studios can do one of two things. First, they can transfer the movie in its original aspect ratio, which induces the black bars. Or they can transfer the movie using the pan-and-scan technique. Pan-and-scan is the "talking nose" way of transferring films and practically ruins a film. Basically, they transfer the film but cutting off a piece of the sides of the movie frame in order to fill the screen. So, if a 2.35:1 aspect ratio film has two characters in the same frame talking to each other, but they are at the edges of the frame, there will be either a lot of panning (scrolling from left to right and right to left) to capture the characters talking or you'll only see the nose of one character. This ruins the vision of the filmmaker. Now, the 16:9 aspect ratio of the current TVs is because of HDTV taking on a more wider ratio in order to gain viewers from the movies. The aspect ratio 16:9 is close enough to 1.85:1 that for 1.85:1 transfers there will be no black bars at the top and bottom of the picture. The only time the black bars shows up is when a 2.35:1 (a much wider film aspect ratio) is shown on a 16:9 screen. The other reason that 16:9 TVs are better is that they allow for the movies to be presented in anamorphic mode. Basically, most DVDs today are made anamorphic. To understand anamorphic DVDs, you'll need to know that all DVDs are made to the standard resolution (525 horizontal lines) of a TV at the standard aspect ratio (4:3). The image that you see on the screen of the TV is formed by drawing the 500 lines of resolution from left to right. Now, say you have a 2.35:1 aspect ratio film, which has black bars at the top and the bottom. All that black bar space is wasted space. What if you took the image and stretched it up and down to fill in most of that space (up to the 16:9 ratio)? Then you would have more horizontal lines of picture in that same frame. Now, for regular 4:3 TVs you'll see no difference since the DVD player takes that stretching and removes the lines of extra resolution to make the picture look correct for the 4:3 aspect ratio. But for 16:9 aspect ratio TVs, they take that whole 4:3 picture and stretch it vertically so that it fits the TV screen, that makes the picture a lot sharper because you have all that extra horizontal lines of resolution. Here is a good presentation on anamorphic transfers and why they are better. I hope this made sense to everyone because there is a reason for why there are black bars and for why there are 16:9 TV sets. And also for why black bars still show up for the "widescreen" 16:9 TV sets. It is a shame that some people choose to talk about technology without first finding out what it all means and why.