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SEPTEMBER 04, 2003 DVD for Designers
File types, dimensions, aspect ratios For graphics creation for DVD, most common file formats will work, but the .PSD (Photoshop) file format has become essentially the standard for DVD graphics. It's used for every element mentioned above, except perhaps transitions/effects, which obviously require some sort of motion graphics program. We can get into that at a later date.[an error occurred while processing this directive]The files themselves vary in size depending on the type of graphical element. All DVD graphics are 72 DPI, and all backgrounds conform either to a 4:3 aspect ratio (standard television) or a 16:9 aspect ratio (widescreen). Buttons and drop zones can be of any size or shape, as long as they don't exceed the overall dimensions of the project, which we'll get to presently. Now, there's always some confusion about the dimensions of images that will be used on television. This is owing to the confounding issue of pixel aspect ratios. Computer screens use square pixels, while television screens use rectangular pixels. And therefore the graphics you create on screen will look scrunched vertically when they're placed into a video editing or DVD authoring program. However, this issue is a bit overblown. Most authoring and editing programs today know how to convert automatically between square and non-square pixels. So, as long as you work at the proper 4:3 or 16:9 aspect ratio, you'll be doing fine. Photoshop itself includes presets for these "starting sizes," which are 720 x 534 for 4:3 and 864 x 480 for 16:9. Which one you use will depend on whether your client is producing a widescreen or standard-format DVD. Note that these dimensions refer to NTSC only, the television standard used in North America and parts of Asia and Central and South America, including the United States, Canada, Mexico, Japan, South Korea, Taiwan, Chile, Nicaragua and others. Note also that some systems use slightly different starting dimensions. The ones listed here are for one of the more common DVD authoring programs, Apple's DVD Studio Pro. Always talk to your client about matter like this before getting started.   Preset NTSC DVD 4:3 dimensions in Adobe Photoshop After you've created a graphic at these dimensions, you can either leave them as is, relying on the authoring program to reinterpret them, or you can squish them down manually in Photoshop. Both will be resized to 720 x 480 for DVD production and/or editing. But don't worry about the distortion. The images are scaled back up to their proper 4:3 or 16:9 aspect ratios when played on a television, and everything looks groovy. "Safety" zones All of that said, with television, you can never take for granted that you have the entire canvas to work with. Why? Not all televisions display images the same way. There's always some variable portion of the image that's cut off the screen. You've probably noticed this in sports events, when the score might be cut off at the top, or on television news, where the stock ticker may be cut off at the bottom. The same goes for credits, graphics and titles on older television shows. The way you compensate for this is to use the generally accepted standards for title and action "safety." These are zones that will, in almost every case, provide you with a safe area to work with for displaying your titles and backgrounds. Anything that's of interest should not be positioned beyond these boundaries. Your background, of course, will extend beyond them, but important elements of your graphics should not. So what are the boundaries? For action, the rule is to use 90 percent of the total canvas area; for titles, the rule is to use 80 percent of the total canvas area. (In designing graphics for television viewing, title safety is the one you should be interested in.) Many programs have built-in title safety generators, so you don't have to create them manually. However, Photoshop does not. For this reason, I have created a set of automated Actions for Photoshop that will generate these safety zones for you. You can download and read about this set of Actions here.  Title and action safety zones, as seen in Photoshop Black and white aren't black and white And, finally, there's the issue of "safe" (or "legal") colors for television. What does this mean? It means that television has trouble displaying certain colors, especially reds and any colors that are over-saturated. When watching television, you've probably noticed that a lot of the end tags ("Call now for your special bonus offer!") cause color bleeding on your screen or may even produce an audible buzz. This is owing to the fact that the colors used by the graphic artist weren't "legal" for television. Here is a general rule for the colors you should use when creating graphics for television.
You can adjust some of these problems using the NTSC filter in Photoshop or adjust the Levels output to 16 on the low end and 235 on the high end. This won't solve everything, but it will help. Contact the author: Dave Nagel is the producer of Creative Mac and Digital Media Designer; host of several World Wide User Groups, including Synthetik Studio Artist, Adobe Photoshop, Mac OS, Adobe InDesign, Adobe LiveMotion, Creative Mac and Digital Media Designer; and executive producer of the Digital Media Net family of publications. You can reach him at dnagel@digitalmedianet.com. Prev 1 2 3 Related sites: • AV Video • Creative Mac • Digital Media Designer • Digital Post Production • Digital Producer • Digital Video Editing • DVD Creation • Film and Video Magazine • The WWUG Related forums: [an error occurred while processing this directive] 
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