Whether you’re starting from scratch or you’ve dabbled in video, there is a lot of terminology associated with recording types that can just make your head spin. You might see a video record format written as 1080i or 720p, for example. You also might hear the terms “sixteen by nine” or “four by three” thrown around. Let’s take a look at some of these terms and help break it down a little bit:
Image size/resolution: Standard definition (SD) video is 720 x 480 and referred to normally as just 480. High definition (HD) video has two different sizes, 1080 x 720 (referred to as 720) and 1920 x 1080 (referred to as 1080). Ultra-HD video sizes range from 2048 x 1152 (2k) to 5120 x 2880 (5k). These differences in size refers to the number of pixels present in an image and the more pixels present, the higher the quality. If you were watching something on a very small TV, the size of the video might not make that much of a difference. If you’re watching on an extremely large TV, however, the size of the original video is very important and if the video is too small for the screen, you will notice quality loss.
Scan rate: After the video size, you might see either an “i” or a “p” such as 1080i or 720p. This letter designation stands for either interlaced or progressive, respectively. These are different scan types which means that you are either seeing full frames of each video (progressive) or seeing half frames at a time (interlaced). With interlaced, the even lines of the video show up first with the odd lines coming in after. You might notice distortion at points where there is a lot of movement because you’ll accidentally see sets of lines from different frames. Progressive requires more bandwidth but it also presents full frames each time instead of taking the interlaced shortcut.
Aspect ratio: You’ll typically hear aspect ratios as either 4:3 (said “four by three”) or 16:9 (said “sixteen by nine”). The first number refers to the width of the picture and the second refers to the height. Old TVs used to be 4:3 but almost anything you purchase now is going to be 16:9. Movies are filmed in an even wider format, 21:9. These ratios are measured in units but their actual sizes differ.
Frame rate: Since video is really just a series of stills, a video’s frame rate refers to how many frames (or still pictures) occur within one second of video. Different frame rates are used for different purposes. In film, 24 fps (frames per second) was typical and you’ll often hear people refer to the “filmic look” which refers to its special frame rate. Standard video is 30 or 60 fps and slow-motion film has raised the bar even higher from 120fps to 250 fps for a regular camera. Above that, they make special slow-motion cameras that can handle even more and as technology advances, so do slow-motion videos! The more frames per second you have, the more intricate slow-motion footage you can capture.
NTSC vs. PAL: These refer to two different video standards. In the US, we use NTSC but many other countries use PAL as their standard. While this means a number of different things, the most notable is the frame rate. The NTSC standard frame rate is 30 frames per second and PAL’s standard is 25 frames per second.
All of NCTV’s cameras record in HD and while we haven’t ventured into the world of 2k+, we’re still fairly up-to-date. Even though we record in HD, we broadcast our channels in SD. Check our YouTube channel for the HD version, however!