In Photoshop CS6 I just rendered a video twice with two different settings. First one was with the Vimeo HD 1080p - 1920x1080 Preset. In the Second rendering I used the YouTube HD 720p - 1280x720.
Both renderings came out with the correct screen size but the file size are exactly the same 120MB.
Shouldn't the YouTube video be way smaller in file size than the Vimeo???
Thanks in advance, any help is much apreciated.
It may be the way your hard drive allocates blocks of data.
The resulting file size depends on the datarates used, GOP patterns and a million otehr things. H.264 being a visual, adaptive compression, also things like the distribution of colored areas, edges and so on in the picture matters. Depending on which of the above come into play, even hugely different settings can result in similar file sizes. So more or less what you see is probably normal.