We're following a bit of a theme here: ProRes versus in-camera recording. Here's an extremely interesting clip with a split-screen demonstration of ProRes vs a Canon C100's internal codec which is 24Mbit/s AVCHD
Our usual caution here applies: you're watching this through the veil of Vimeo comparession, which is - with all respect to Vimeo - like looking at the Mona Lisa through a beer glass. But you can see a difference and it's quite significant in this case.
It's worth mentioning that this test uses moving foliage as its subject, which is notoriously difficult to capture using Long-GOP codecs like AVCHD. So you do have to treat this as something of a worst possible case. But it's exactly this type of case where you might want to consider using an external recorder (an Atomos Ninja 2 in this case)
There's no criticism of Canon intended by pointing this out. It's actually a testament to the quality of the camera and lens that you can capture a significantly better image if you take the uncompressed feed out of the HDMI socket: all a recorder can do is capture whatever it is fed.