Creating Smaller Screen Capture Recordings On a Mac

When you record the screen for a long period of time, the file can be huge. But by using third-party software like OBS Studio, you can record directly to a compressed file at a fraction of the size, only sacrificing a little of the quality.
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Video Transcript

Hi, this is Gary with MacMost.com. Today let me show you how to make smaller screen recordings.
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So this is a question I commonly get asked. Screen recordings can be really big. If you're just going to record a screen for a few minutes and maybe keep it around temporarily it's no big deal. But if you're going to record for 10, 20, 30 minutes your entire screen that file can get huge. It's recording every pixel on your display for every frame. So is there an alternative? Well, you can use a third party app and one such app is the free OBS Project Software. But first let's try a regular screen recording.
We start off here with a nice big Finder window and open something to record. I'm going to do Shift, Command 5 and it's going to bring up the recording controls here at the bottom. I'm going to select Record Entire Screen. Under Options I'm going to have it save it to the Desktop. I'm going to have No Timer and I'm not going to get any microphone input. I'm just going to hit Record. I'm going to record this display IF2 and now it's recording. I'm going to scroll down and scroll back up so its got something to record. I'm also going to switch to Photos and have a slideshow ready to go. It's going to run that slideshow. It's going to run through six images with a transition between them. So now it's got something to actually record and save. That's that. Let me escape out of the slideshow there. Hide the Photos App and I'm going to Stop the recording. 
Now I can see I've got a file here. If I use Command i, I can see it's a 105 MB. 
Now let's try it with OBS Studio. If you don't already have this software it's great. It's like a little broadcast studio on your Mac. It's completely free open-source software. You can just download it. There's a bit of a learning curve as you could expect because it's very powerful. So here's kind of what it looks like. This is showing what you're seeing here. You have scenes that you can create. So you want to record the screen. So you can create a simple scene. I'm going to hit the Plus button here. I'm going to call it Screen Recording. Screen Recording doesn't have any sources. There's nothing to show. So I'm going to click the Plus button here and I can choose from a variety of sources. Microphones, cameras, all sorts of things. I'm going to choose Display Capture. I'm going to create a new Display Capture. Okay. Now you can see it's capturing the display actually creating this interesting infinite effect here because it's capturing itself. I can choose the display and I can choose whether or not to show the cursor. Click OK. Now you could see this area here is actually showing the entire display like that. 
I'm going to click on Settings here. For Settings I'm going to go to Output. Now I can control the quality of the video. This is what will make it smaller. If you want a smaller file size you have to sacrifice some quality. So I could say instead of capturing every pixel I want a certain bit rate. 2500 kilobits per second. You can also set the recording quality here. So let's choose high quality medium file size. Then I can choose the format. I'm going to leave it at MP4 and at 264. So it's going to do MP4 H264 quality which is pretty standard. Then OK.
Now another thing I've got going on is that what it's capturing is a lot bigger than the space here. Let's go into Settings again and then Video Settings and we can see it set to 1920 by 1080. But that's actually not the entire screen. The entire screen, as I have it set now, is this size. So let's change it to that. Now I can take the rectangle here, that is the whole screen, make sure it's centered here on the scene and now it should record everything. So I could just start recording here. I can also hide this and then use the Menu Bar button here and start recording. I'm going to do the same things as I did with the other recording. I'm going to scroll through this list here and go up to the top. I'm going to bring the Photos App to the front and run through this slideshow and let it go through the six slides with the transitions. Now that's done. I'll Hide Photos here. I will go in here and Stop recording. You can see I've got this file here that's been created.
Let's go and take a look at that. I'm going to select it and do Command i. I can see here 13.7 megs. So an order of magnitude smaller than the 100 some meg file from the regular screen recording. Now let's compare these files properly. I'm going to go here to the Desktop and I can see the two files. Let me bring up the Preview and shrink this window a bit. Now I can see here on the right that this regular screen recording, 2560 by 1440, is 46 seconds long and it's a 105 megs. This one is also 2560 by 1440. It's a little bit shorter. I didn't record quite as much. It's less than 14 megs. Now let's double click on this one here and I can see the quality. It's not going to be perfect. It is slightly compressed. But it's really hard to tell. You could see everything in here looks good. Now let's compare it to this, a much smaller file. I can definitely tell it's not quite the same quality. But it still looks pretty good. So a much smaller file only sacrificing a little bit of the quality.
So of course using OBS is not your only option. There are lots of third party apps that will do screen capture like this and allow you to set the quality level so it records directly to a smaller file. OBS does have the advantage of being open-source and free so it's really easy for anybody to access. Plus it's a really powerful tool so learning a little bit about it is probably a good thing. Of course another option would be to actually just screen record normally with the built-in tools. Then once you have it in Quick Time Player you can export it As and then drop it down to a smaller size or you can use a compression tool like Apple's own compressor to compress that file. 
I know a reason a lot of people want to record to an initial file that's much smaller is because they don't have enough hard drive space to record the screen for 15, 30, or 60 minutes. It's just too big of a file. So you couldn't get that large file to compress it even if you wanted to. I hope that this helps some people out. Thanks for watching. 

Comments: 2 Comments

    Razvan Mihai
    4 years ago

    Gary: Another drawback of using Quick Time is that the audio is recorded from the mac output speaker. With OBS, is there a way to route the audio signal in such a way as to capture the original audio input?

    4 years ago

    Razvan: Computer audio is not recorded with macOS screen capture at all. Well, your mic can pick up the sound from the speakers, but that's not really a good way to do it. You can use a third-party app to re-route the computer audio to either macOS screen recording or OBS. See https://macmost.com/how-to-record-your-mac-screen-with-audio.html

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