Learning Center : Formats Explanation
Shape Shifters Part 2 : Aspect Ratio Solutions
by Greg Robinson/Electronic House
This is a continuation of last week’s article: Shape Shifters Part I.
If you’re like most front projector owners, you probably have a 1.78:1 or “HDTV” aspect screen, the same shape as most widescreen flat panels. When watching a wider movie like Inception, the easiest way to eliminate the letterboxing effect is to simply cover the black bars on your screen so you can’t see them. Depending on how good your projector is at rendering black, staring at charcoal gray stripes for two hours can be infuriating.
Screen masking systems operate by remote control and cover the black bars with a light-absorbing, fabric-covered shade, thereby making your movie look as though it’s filling the entire screen.
Screen manufacturers offer a variety of masking systems, some horizontal, some vertical, and some with both. Most are motorized and can be programmed to function as part of a universal remote’s macro command sequence. Masking systems can greatly improve the viewing experience, but it’s important to remember that you’re simply covering up the problem. Like a throw rug over a grape juice-stained carpet, those black bars are still there – you just don’t notice them.
Screen Side: Cinemascope Screens
The 2.35:1 aspect ratio, commonly called “Cinemascope,” is probably the most common aspect ratio when it comes to Hollywood’s modern blockbusters. Films like Gladiator, Braveheart, Alien, Star Wars, Blade Runner, Iron Man, Batman Begins, The Incredibles – all of them feature the Cinemascope aspect ratio. If you’re more of a movie watcher than a TV watcher, you may want to consider a screen shape that matches what you like to watch most often.
Most screen manufacturers now offer screens with aspect ratios of 2.35:1 (or 2.40:1) and these ultra-wide screens have the benefit of perfectly matching your favorite Hollywood films. It should be noted though that while you can use a Cinemascope screen with any 1080p projector, zooming the lens until the movie fills your screen, you’re in for a few headaches when watching non-Cinemascope content. For this reason, a Cinemascope screen makes the most sense when paired with an anamorphic lens system. More on that in a minute.
Zoom Lens Memory
On the subject of zooming, one solution that’s popular with the DIY crowd is the use of a Cinemascope screen paired with a projector featuring zoom memory for 2.35:1 applications. Projectors such as Panasonic’s PT-AE4000 will allow you to program a zoom adjustment that enlarges your projected image until the 2.35:1 movie fills the height of your screen.
Simply use vertical side curtains in front of a Cinemascope screen to create a 1.78:1 screen for day-to-day HDTV viewing. Then, when it’s time to watch Braveheart, slide open the curtains to give you a wider screen, activate the projector’s zoom memory, and you’re now viewing a much wider image, using the full height of your screen. Take note though: although you’re using the full height of your screen, those black bars are still being generated by the projector. You are not yet using the full vertical resolution of your projector. This is an important distinction to understand.
Anamorphic Lens Systems
Many of today’s front projectors have the ability to output video in a vertically-stretched or anamorphic viewing mode. Manufacturers vary in how they describe this feature, but as a rule, look for mention of anamorphic lens compatibility. As an example, here’s a bullet point from one company’s spec sheet: “Compatible with 4:3, 16:9 and 2.35:1 (with anamorphic lens option).”
You may be familiar with the anamorphic stretched look if you’ve ever tried watching an anamorphic widescreen DVD or Blu-ray Disc on a non-anamorphic display, where people and objects appear tall and skinny. This is how things will look when you engage this mode on your projector. You wouldn’t want to watch your movies this way, but notice that those black bars are now gone. You’re now using 100% of your projector’s vertical resolution.
To make everyone look right – while maintaining full vertical resolution – the final step is to introduce an anamorphic lens in front of the projector’s lens. This prism-based device will stretch your content horizontally, thereby restoring the already-vertically-stretched video to its proper size and shape. The lens can be slid into or out of position either manually, if you have a low ceiling, or you can opt for a motorized assembly if you prefer the fully-automated route.
Fixed Height Systems
At last we come to the Holy Grail. To enjoy the cinematic experience of a Cinemascope presentation AND maximize your projector’s full potential during your favorite movies, the solution lies in the combination of several elements we’ve already discussed. First, we need a Cinemascope screen, either 2.35:1 or 2.40:1. Next, we’ll want to employ a vertical masking system (read: “curtains”) to frame non-Cinemascope content such as 1.78:1 prime time TV. Finally, we’ll need an anamorphic lens system to make full use of that Cinemascope screen AND our projector’s resolution capabilities.
This blessed combination of elements is what’s known as a “fixed height” or “constant height” system. Using different projector output modes, your screen height will never change. The only thing that will change is the width – and that’s where your vertical masking comes into play.
Projector adjustments, masking systems, lens sleds – seems like a lot of work, doesn’t it? Compared to a flat panel display, yes – a fixed height Cinemascope screen system featuring an anamorphic lens is definitely more involved. It’s definitely taking your home theater to the next level. But isn’t that sort of the point? Casual TV watchers aren’t going to install a system like this. A fixed height system is for diehard movie lovers like you and me. And when the lights go down, and Star Trek starts blazing across that oh-so-wide screen you now have… oh my.
Related: anamophic, Anamorphic Lens Systems, Batman Begins, Blade Runner, Fixed Height Systems, Home Theater, Iron Man, Lens Solutions, Masking Systems, Runco, Screens, Shape Shifters Part, Star Trek, Star Wars, TV, Zoom Lens Memory shapeshifters solutions