Bryan's DVI vs. Component HDTV Input Page
I recently switch from using a component video connection to a DVI connection for my HDTV viewing. During the Monday Night Football broadcast on November 29, 2004, I snapped a couple of images of ABC's scoreboard to demonstrate the difference between the two connections.
Component HDTV connections are actually analog. Since my DLP television set is by nature a digital technology, there is a DIGITAL -> ANALOG -> DIGITAL conversion going on between my HDTV receiver and my TV. The DVI connection is all digital from start to finish, and is what you might call "pixel perfect", especially in this case where the resolution of the broadcast is at the native resolution of my TV, as ABC broadcasts in 720p.
Click on the images below to get an enlarged view.
The first image is from a SA3250HD digital cable box, set to pass through the 720p signal, connected to my HLM507W TV via DVI. Notice how clean the "1" is -- how the main vertical part of it is exactly 4 pixels wide, all the way up.
The second image is from an SIR-T150 OTA receiver, set to pass through the 720p signal, connected to my HLM507W via a component video connection. Notice how the image is not as perfectly clean. The blotches, by the way, are not static, but dance around, a bit like noise.
From 7 or 8 feet away, there isn't quite as obvious a difference as it is on these super-close-up still images, but there is definitely a clear and obvious improvement in the clarity of the signal.
Though I'm pretty sure you'll get similar results from other inherently digital display technologies (like LCD), you may or may not get a whole lot of improvement on displays that are inherently analog, such as ones that use CRT's. In this case, I would imagine it depends on whether your TV is better at converting the digital signal to analog than your sorce (ie. your HDTV receiver) is at converting the signal from digital to analog.
Obviously, this isn't exactly a scientific experiment -- I'm using signals from two different receivers, which receive the broadcast in two different ways. However I can say that there is a similar difference in picture quality between the two connection types when using only the SA3250HD cable box. It's just that it'd be a major pain in the butt to do a back to back comparison of the two connection types off the same box as the 3250HD disables the component video output whenever the DVI cable is plugged in.
By the way, in case you were wondering, I am not experiencing problems with the picture geometry of my TV set -- the bulge you might notice in those images is due to my camera's wide angle lens... Maybe one day I'll try and get some better images.
One last (further more unscientific) thing -- I went back 2 weeks later to get a comparison shot of the scoreboard, but in standard definition. This is the Monday Night Football scoreboard as it looks on my setup via cable TV... I guess I wanted to illustrate that even though DVI is cleaner than component HDTV, that component is still WAAAAAAAY better than standard definition TV!!
Last Updated November 30, 2004