Aspect Ratios vs. Resolution

Evan Powell, August 22, 2003

Frequently Asked Question:

Doesn't a native 16:9 projector deliver more resolution for 16:9 viewing material than a 4:3 projector? If so, shouldn't I go with a 16:9 projector if I want the best possible HDTV resolution?

Answer:

Contrary to conventional wisdom, the answer is no, not necessarily. This issue requires a little creative thinking. Why? Well, consider this: the highest 16:9 physical resolution available at this writing on ANY projector under $10,000 is delivered by a native 4:3 format projector. That would be the JVC DLA-SX21 aka Dukane 9017, which has a resolution of 1400x1050. That of course is native 4:3.

On this JVC/Dukane projector a 16:9 image is created using a 1400x788 matrix. Do the math and you will find that this projector has 20% higher physical resolution than you get from any of the Mustang/HD2 DLP projectors that are native 16:9 (1280x720) and selling in the same general price range. So if pure physical resolution of the display for HDTV is what is most important to you, the 4:3 format JVC/Dukane projector trumps all of the 16:9 machines on the market at this time.

Here is another example--the new InFocus Screenplay 5700 is native 16:9, with a physical resolution of 1024x576. Meanwhile the NEC LT240K, selling at half the price, is native 4:3 XGA resolution. And it produces a 16:9 image with precisely the same physical pixel matrix, 1024x576, as does the Screenplay 5700. So does the fact that the 5700 is native 16:9 give it a resolution advantage over the LT240K? Not at all. The LT240K delivers equal resolution for 16:9, and higher resolution for 4:3 than does the 5700.

Now, of course in the same general price range as the Screenplay 5700 you can find the Sanyo PLV-70, a 16:9 machine with much higher physical resolution (1366x768) than the 5700. And currently there is no 4:3 format projector in that price range that is capable of matching the PLV-70's 16:9 resolution. So if you want to spend about $5,000, the native 16:9 PLV-70 does in fact offer the highest possible 16:9 resolution for that amount of money.

Furthermore, at the very low end of the budget range it is always true that 16:9 machines deliver higher 16:9 physical resolution than 4:3. That is because the cheapest projectors on the market are native 4:3 format with SVGA resolution. On these machines a 16:9 image is produced using an 800x450 pixel matrix, and you cannot get any lower than that these days. Even the least expensive 16:9 units such as the Panasonic PT-L200U use an 858x484 display, which beats any standard SVGA machine.

The point of this discussion is to illustrate that the resolution question is not as simple as it might appear at first. It is not always true that you get the highest 16:9 resolution for the money from a 16:9 projector. So why the confusion? It derives from the natural tendency to compare 4:3 and 16:9 resolution capability within the context of a given projector. Obviously a native 16:9 projector will use more pixels to produce a full frame 16:9 image than it will a native 4:3 image. Conversely, a native 4:3 projector will use more pixels to produce a full frame 4:3 image than it will a 16:9 image. This causes many folks to erroneously presume (understandably) that 16:9 projectors as a class always have a resolution advantage over 4:3 units for HDTV and other widescreen material.

As you plan your home theater, you will do yourself a big favor by separating the aspect ratio decision from resolution decision. They are two different and independent issues. Furthermore, the aspect ratio decision is huge. How you decide to set up your theater to display 4:3 and 16:9 sources will be in your face every day for the life of the system. You will live with the advantages and limitations of whichever set up you choose. Relatively speaking, the resolution question is of lesser consequence—no matter what projector you choose you will quickly become accustomed to its resolution and get into the enjoyment of the image without much fretting over how many pixels there are on the screen.

Therefore we encourage you to examine the aspect ratio question first. Ignore resolution as a factor. Determine how you will want to stage 4:3 and 16:9 material in your theater. After deciding this, then you can search for the ideal projector that will deliver images the way you want to see them. And the ideal projector will be decided by a host of performance factors, including not just resolution, but aspect ratio, brightness, contrast, intended usage, overall video quality, price, and so on.