Prior to the digital age, one of the joys of editing was the ability to take the workprint off the flatbed, mount it on a projector, and watch it on a large screen. This served an important step in the editing process, allowing you to approximate the rhythm and pace of a scene as it would feel in a theater. You could also see image and performance issues not apparent on the small flatbed screen.

Digital editing has not lent itself to such critical evaluation. Even a huge 30" monitor pales in comparison to watching your work projected on a ten foot movie screen. This all changed with the influx of affordable digital projectors. For many years digital projectors were expensive, starting at about $5,000. Recently, however, the price of HD (high definition) projectors has fallen below $750!

We've reached the final frontier in the digital revolution. Now, you can shoot, edit, and project high definition digital images in direct competition with major players.

Optoma Model HD20

Today's digital projectors feature quality construction and portability. Many are not much bigger than a cigar box. There are several technical differences between models that you should be aware of before purchasing one:

LCD vs. DLP Technology

In an LCD projector, the video signal is split into three light beams--red, green, and blue. The beams strike a corresponding LCD panel (liquid crystal display), which regulates the beam's intensity, similar to the way a venetian blind works. The three beams are then recombined and directed through the projector lens.

In DLP projectors, the light beam is reflected off a DMD chip (Digital Micromirror Device) though the projector lens. The DMD is made of millions of tiny mirrors that fill a designated pixel space on screen. The mirrors have the ability to tilt and switch on/off, depending on the pixel's gray scale requirements. Hue is added using a spinning color wheel with red, green, and blue segments.

Which technology is better? Since each has its pros and cons, it's hard to say. LCDs tend to be brighter with great color saturation. DLPs tend to have richer blacks and contrast. LCDs are more prone to visible pixels (pixelation), while DLPs occasionally produce a rainbow effect from the spinning color wheel.

The higher up in price you go, the less apparent the quality difference between the two technologies. Ultimately, the question of which is better boils down to personal taste.

DLP projectors use a proprietary technology developed by Texas Instruments and licensed to key manufacturers like Optoma. The major developers of LCD projectors are Sony and Epson.

Resolution

HD projectors are available in 720 and 1080 lines of resolution. 720 projectors are cheaper and will most likely disappear from the market as the price of 1080 projectors continues to fall below $1000.

SD (standard definition) projectors are considerably less expensive but the resolution is only 480 lines. This is not enough for quality big screen projection so avoid them.

HD projectors can be distinguished by the HDMI inputs, as illustrated below. HDMI has replaced component video as the input port of choice, though most projectors still have both types.

Operation

There are two types of digital projectors: stand alone and all-in-one. Both are simple to use.

Stand alone projectors, like the model shown below, are simply that--projectors. The source video, whether DVD, video deck, or computer, is plugged in to it.  Some models have speakers but most do not, so the sound must be routed from the video source to an external amplifier.

After the initial setup, operation is straightforward. You turn the projector "on" and control the video from the source machine.

If you need true portability, an all-in-one projector is the way to go. In addition to the traditional input ports shown above, this design features a built-in DVD player and speakers. The setup involves simply plugging it in and turning it "on."

All-In-One Projector - Epson Model 72

Purists may scoff at the idea of an all-in-one projector, but they serve an important function, particularly if you need a simplified setup and/or high degree of portability.

Image Quality

Expensive digital projectors have been around for years and the quality is difficult to discern from film. Chances are you've seen a digitally projected movie and not realized it. The challenge for manufacturers was to bring theater quality to the home and prosumer markets.

The current crop of entry level HD projectors is truly amazing. Images are bright with rich colors, wide contrast, and deep blacks. They really pop out at you, as you can see in the screen capture below.

Optoma HD20 Screen Capture

These projectors can fill a screen measuring up to 25 feet across. To achieve optimal quality you must use an HD or Blu-Ray DVD player.

If you are using standard definition DVDs, an upscaling DVD player will yield surprisingly close results. The upscaling player converts SD video (480 lines) to HD (1080 lines).  Most DVD players today are upscaling and inexpensive, starting at around $75.

If the image still suffers, chances are it's the DVD itself. You may not realize it, but transfer quality varies even among major distributors. This occurs because some transfers are made with too much compression, either by choice or because too much information is being crammed on to the disk.

When the video image is overly compressed, it results in artifacts. You will see pixels blocking up in groups or dancing around sections of the screen.

An example of this is found in Disney's Platinum Edition of Beauty and the Beast. It was touted as being a beautifully remastered transfer. Despite lush colors, the video itself is marred with artifacts, the result of compressing three versions of the film on to a single DVD.

Editing Course Topics

If you are interested in learning more about the movies used  in this
 lesson, click on the title or picture (courtesy 20th Century Fox,
MCA/Universal, Paramount, TCM, and Warner Brothers).

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