There is a lot of planning and thought that goes into a creating screencast. Determining your ideal screen resolution is an important factor to consider before you start your recording. Here’s a quick overview of what it is and why it matters.
First things first: What is screen resolution?
Screen resolution is a measure of how your monitor or screen displays an image; it essentially refers to the clarity of the content on your screen. Most LCD screens use pixels (tiny square or rectangular dots) to display text and pictures onscreen. These pixels are measured across and down the screen, and are usually shown as something like “480×360”, which means there are 480 pixels across and 360 pixels down. This measure of pixels is known as “resolution”.
As you can imagine, if you are looking at two screens of the same size, and one has a higher resolution than the other (1600×1200 would be a higher screen resolution than 640×480 for example), the content on the one with the higher resolution will appear sharper and clearer. There are more pixels there to represent the data.
At higher resolutions, the pixels are more numerous and smaller, so as a consequence the items onscreen will also appear smaller, with more items fitting on the screen. At lower resolutions, there are fewer pixels so the items on screen will be larger and fewer items will fit on the screen. At very low resolutions, images might look “pixelated” or have jagged edges, because there are not enough pixels to provide a crisp, clear image.
What is aspect ratio?
Related to screen resolution, and another thing to consider when screencasting is your screen’s “aspect ratio”, which is the ratio of its width to its height. Every screen resolution has an aspect ratio associated with it. A few of the most common aspect ratios we see today are 4:3 (pronounced “4-by-3”, or “4-to-3”) and 16:9. Another way to represent this is to divide each number by the height, so a 4:3 monitor is also known as a 1.33:1 display (4/3=1.33, and 3/3=1). In other words the display is 1.33 times as wide as it is high. A 16:9 monitor is also known as 1.78:1.
You can easily figure out what aspect ratio a resolution is by dividing the first number (the width) by the 2nd number (the height).
For example: 640 divided by 480 = 1.33. You may notice this matches the number for the 4:3 aspect ratio above, meaning this screen resolution (640×480) displays at 4:3 aspect ratio. As another example, a resolution of 1024×576 would display as 16:9 (1.78:1).
Why do screen resolution and aspect ratio matter?
It’s quite simple: If the resolution or aspect ratio of your video doesn’t match the resolution and aspect ratio of the display on which you want to show it, your video may appear cut-off, distorted, too small, or too large. When you see horizontal black bars at the top and bottom of a video (called “letterboxing”) or vertical bars on either side of a a video (called “curtains”), that’s an example of a video that was recorded at a different aspect ratio than it is being presented. This wastes screen real estate, and potentially lowers your video quality.
Not only that, if you record something at a high resolution (say 16:9 1440×900) that you want to display on a smaller screen at a low resolution (say 854×480), the type and images onscreen are going to be so small they may be unreadable for your viewers. So if you don’t have an understanding about screen resolution you could end up with a low quality, unreadable video!
In the image below, I’ve tried to show the potential problems when you record in one resolution and display in a different resolution. If you record and export at high resolutions, the smaller you display that content, the smaller all the text and images become – to the point of being unreadable. (Shown in the bottom triangle of the image below.) But on the other hand, if you record and export at a low resolution and try to display that on larger monitors or displays, the more fuzzy your content will be. (Shown in the top triangle of the image below). If you’ve ever tried to watch a 320p YouTube video on full screen, you’ll know what I mean.
Here’s a table from TheScreamOnline that also shows the how resolution and screen size are linked.
Putting this knowledge to practice: A few tips and best practices
- For best results, record at exactly the same target resolution at which you want to display. For example if you’re producing 16:9 720p, you should record 1280×720 pixels, and you should set your monitor to that resolution.
- Presentations, images, and videos can be created in any aspect ratio, therefore it is important for you to be aware of your target resolution and aspect ratio during planning so you can create all your original content at a consistent size and ratio that will display correctly on your target.
- If you must scale your screencast, then make sure at the very least you keep the aspect ratio consistent from recording to export. If you are targeting 4:3, record at 4:3. If 16:9, record at 16:9.
- For example if you have a Keynote presentation at 640px x 480px (a 4:3 ratio) that you want to record and display as a video on your website that has a width of 500px, then you should export your video at 500 x 375 (500 divided by 1.333 = 375) to keep the same ratio size.
- If your monitor doesn’t allow you to record at your target aspect ratio/resolution, then use the Canvas Size adjuster in ScreenFlow to change the aspect ratio of your screen in post production, so when you export, you’ll be exporting the proper aspect ratio.
- Keep in mind, also, the larger the resolution, the bigger the file size. So don’t automatically assume that a higher resolution screen recording is going to be better for all situations. If you only need to display at 480 x 360 then recording a video at 1024×768 will only inflate the size of your file. Reduce your screen resolution and you’ll be able to also get your file sizes down.
One person I know records his videos in 1280×720 and exports in 960×540. For him, this offers a high quality “master” copy, that then exports with a nice balance of quality, readability and screen size for his target displays. You may have a different size that works best for you – but it will depend on where your videos are displayed and for what audience. Test out some different sizes and see what works for you.
Here are some commonly seen 4:3 resolutions (generally standard definition):
- 640 x 480
- 480 x 360
And some common 16:9 resolutions (known as wide-screen, and generally high definition):
- 1280 x 720
- The 9.7″ iPad display has a screen resolution of 1024×768 pixels
- The iPhone 4 is 960×640
- Standard resolution for DVD format is 720 x 486
- Wide screen DVD format is 864 x 486
- Online video (like YouTube) displays well at several resolutions, but one that works well for me is 1280×720
What screen resolution and aspect ratio do you find works best for your screencasts?