Once you’ve put together some awesome videos, such as our recent Greighwolfe Acoustic Gold, you need to encode it and upload it. Fortunately, Adobe made this much easier with an update back in July of 2014, http://blogs.adobe.com/aftereffects/2014/07/adobe-media-encoder-cc-2014-0-1-update.html, by simplifying the settings available to just 5.
YouTube 2160p 4K (40 Mbps)
YouTube 1080p HD (16 Mbps)
YouTube 720p HD (16 Mbps)
YouTube 480p SD Wide (8 Mbps)
YouTube 480p SD (8 Mbps)
Since YouTube does downsampling automatically, you only need to encode at the largest image size before uploading. And even though this second article is about 3 years old at this point there are still some great tips such as using noise reduction to improve quality, the cleaner the image, the easier time the compression has. Take a read http://www.streamingmedia.com/Articles/Editorial/Featured-Articles/Encoding-for-YouTube-How-to-Get-the-Best-Results-83876.aspx
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