Digital Video Primer

What is the best way to shoot my project? Should I shoot 24p? What is the difference between 1080 and 720 HD? What type of digital video will look most like film? What are codecs? What do I need to know about audio? Should I worry

about transcoding? What do all those other acronyms and numbers mean?

In this chapter, we’re going to introduce you to the fundamentals of digital video technology. Consider this chapter a reference for the terms and concepts you will encounter on a day-to- day basis during your production process, as well as throughout the rest of this book.

What Is HD?

By now, you should have a script and have started to work out what your budget and your shooting schedule will be. And you should have started to make decisions about the way you want to shoot your project. At this point, you probably have lots of questions but one thing should be certain: you are shooting in high definition (HD). Why? Because all digital formats with a resolution greater than standard definition (SD) video are considered HD. In other words, unless you are using old equipment, HD is almost impossible to avoid these days.

HD is a tricky thing to discuss because the term itself does not actually refer to any one particular type of digital video. Rather, it’s a “set” of digital video formats and specifications.

However, when digital filmmakers talk about shooting HD, they’re almost always talking about one of the three primary subsets: 720, 1080, and digital cinema.

n720 has a resolution of 1280 720 and is always scanned progressively. It supports the following frame rates: 23.976p, 24p, 25p, 29.97p, 30p, 59.94p, and 60p. It has a native aspect ratio of 16:9.

n1080 has a resolution of 1920 1080 and can be scanned progressively or be interlaced. It supports the following frame rates: 23.976p, 24p, 29.97p, 30p, 50i, 59.94i, and 60i. It has a native aspect ratio of 16:9.

nDigital cinema is a very high-resolution digital format that aims to be comparable to 35mm film. It has a resolution of 2000 horizontal pixels (usually referred to as 2K) or greater, is progressively scanned, and usually has a frame rate of 24, but some cameras can shoot at variable frame rates.

If the previous descriptions of 720, 1080, and digital cinema leave you cross-eyed, don’t worry. We’ll explain what all that means in the next few pages.

All of these formats are of very high quality. Each frame of 1080 is almost double the size of a frame of 720. However, 720 offers the option of 60 frames per second, which doubles the information of the highest 1080 frame rate (see Figure 3.1) and 2K digital cinema is only a little bigger than 1080 HD. So it can be hard to say exactly which one is a better format.

Digital cinema cameras that record 2K video come with a heck of a lot more than just an extra hundred lines of scan resolution. Their extremely good latitude and dynamic range is what makes them so incredible, in comparison to, let’s say, standard HD cameras like the Panasonic HPX-170 or the Sony EX3. Furthermore, 720p can be described as useful for certain kinds of video production that require long record times, like weddings or corporate industrial videos. On that level, it can sometimes be more about logistics than anything else.