The FYI on NTSC, VGA and ATSC.
Previewing DV clips and other digital source material on your computer monitor is fine if your video project will only be seen on another computer. But if your project will ever be viewed on a TV, many editors find using both VGA (computer) and NTSC (television) monitors an indispensable part of their editing setup.
There are hundreds of quality VGA and NTSC monitors currently available. In addition, displays compatible with the new digital TV standard (ATSC) are hitting the markets. Some feature traditional CRT (Cathode Ray Tube) design, while others are pushing the limits of LCD (Liquid Crystal Display) and other technologies.
So before buying a new monitor, it's best to do some homework on the types available for use in your home-based video production setting and then deciding which one will best suit your needs. The accompanying manufacturer listings will help you sort through it all.
More than a decade after the first successful television transmission, it became clear that a broadcast standard would be needed. The group that created these standards called themselves the National Television Systems Committee, or NTSC for short. This is the broadcast standard in the USA–other parts of the world (predominantly Europe) use PAL or SECAM standard.
NTSC is an analog system, therefore, NTSC monitors do have their drawbacks, especially when dealing with digital images. On an NTSC monitor, images are transmitted via voltage that is affected by heat and cold, connectors, wire length, and more. This can dramatically impact color, brightness and contrast. A computer monitor receiving a video signal through its DVI (digital video interface) connector, however, uses numbers to represent the color and brightnes. In addition, an NTSC signal is chopped up into odd and even scan lines and is interlaced at a rate of 60 times a second. This interlacing is very different from the way your computer monitor handles its signal. So, you can see that the image on your computer screen will not match the one on your monitor. That's why it's important to preview video footage on an NTSC monitor that works like a home television.
Many of the professional CRT-based NTSC monitors available have many of the same basic features. These include a 4:3 / 16:9 switchable aspect ratio, H/V delay, underscan, at least two composite A/V inputs, Y/C and RGB and Y/R-Y/B-Y format inputs. Most of these units use a menu-driven interface generally accessed and manipulated via a remote control or front-panel controls, and are often rack mountable. Most models, however, do not come with speakers and if you're wanting to view in PAL or SECAM formats as well as NTSC, you will pay more. While all features are important, probably the most important feature on any professional NTSC monitor is the ability to manually adjust color settings, brightness and contrast to fit SMPTE (Society of Motion Picture and Television Engineers) standards..
In 1987, IBM introduced the Video Graphics Array (VGA) display system for computers. This VGA system forms the basis for modern display modes such as SVGA, XGA, and SXGA that feature greater resolution and color. However, even today, most computers still support the VGA standard and many video professionals continue to use VGA monitors. Now made to be extremely thin, LCD monitors are good for creating video graphics and generally pull less power than the standard CRT monitor.
Popular VGA monitors include a high-resolution (at least 1024×768, but 1280×1024 is gaining popularity quickly), high-contrast dot VGA panel for accurate signal reproduction. A wide (at least 120 degrees) viewing angle lets you see the image even if you're not standing directly in front of the screen. But LCDs have not yet taken over the world. Some professionals who demand the best color and contrast reproduction still swear by some of the higher-end CRTs. A standard VGA monitor should also include image size and position adjustments and color temperature adjustment capability. Some LCD monitors also include backside brackets for wall mounting. Unlike many pro NTSC monitors, some computer monitors include speakers.
DVI (Digital Visual Interface) is a relative newcomer to the world of computer video, although the standard quickly found a second home in home theater applications for connecting digital TV tuners and satellite receivers to display devices. It provides a completely digital path from the computer to the monitor, bypassing any unnecessary conversions from digital to analog, giving a very clear image with practically no tweaking required. This comes at some cost, though–however, the cost of all LCDs has been slinking down slowly but surely as manufacturing processes become more refined. Using a DVI connection on your monitor also requires having a video card with a DVI output. See the manufacturer's listing for more information.
The FCC chose the recommendations of the Advanced Television System Committee to define the parameters of digital television. ATSC uses the data compression standard known as MPEG-2, achieving a 50-to-1 data reduction which means that when the image redraws on your screen, MPEG-2 does not retransmit areas of the screen that remain the same as they did in the previous frame. The result is a clear, clean, crisp HD image.
ATSC monitors, while not as numerous as either NTSC or VGA style monitors, are perfect for digital editing and graphics composition. While "standards" are still being defined, to get the job done you can expect a native resolution of 1280 x 1024. ATSC monitors should have a standard contrast ratio of 500 to 1 with a wide viewing angle of at least 120 degrees. To find out more about ATSC monitors, please see the manufacturer's listing.
Michael Fitzer is an Emmy™ Award winning writer/producer and a
partner in Blackfish Films, LLC.
TV or Monitor?
So what's the difference between a TV and a monitor? Well, a monitor is essentially a TV without the tuner. A monitor will usually have other controls such as a selector for seeing all of the video information (under and overscan selector). Frequently, monitors also feature rugged design and more precise controls of contrast, color and brightness, and a greater variety and amount of inputs.