For those who are unaware, here are the HD video differences between the two cameras:
| HD Formats | 5D Mark II Frame Rates | 7D Frame Rates |
| 1280 x 720 | - | 60p (really 59.94), 50p |
| 1920 x 1080 | 30p | 30p (really 29.97), 25p, 24p (really 23.978) |
Other notable information for video usage:
| 5D Mark II | 7D | |
| Sensor size | 24mm x 36mm (35mm full frame) | 22.3mm x 14.9mm (APS-C) |
| ISO range | 100-6400 (expandable to 12800) | 100-6400 (expandable to 12800) |
| Shutter speed range | 1/30 – 1/4000s | 1/30-1/4000s (for 1080p24, 1080p25 and 1080p30) 1/60-1/4000s (for 720p50 and 720p60) |
Clearly, the 7D is the more capable of the two from a video standpoint other than that humongous sensor of the 5D Mark II. That enormous sensor is a game changer – In a camera that costs less than $3k. The large sensor is larger than a Varicam, larger than a 35mm movie camera, larger than an Arriflex D-21 and larger than a RED! Some say that the reason the RED Scarlet has been delayed (dragged back to the drawing board actually) was the release of the 5D Mark II.
Both the 5DMkII and the 7D have similar dynamic range and both use 14-bit sensors. The sensor is where they differ. While they have similar resolutions (18 MP for the 7D versus the 5DMkII’s 21 MP), the 7D’s smaller sensor means that the pixel pitch is smaller at 4.2 µm compared to the 6.4 µm of the 5DMkII. In real terms, this translates to worse low-light performance for the 7D (the SNR for the 7D is almost 4 dB worse lower than the 5DMkII according to DxOMark, which I encourage you to play with.) The smaller sensor size of the 7D also introduces a crop factor or focal length multiplier (depending on your preference) of 1.6.
So to sum up:
The 7D gives you 720p and 1080p with a range of frame rates and a 1.6x focal multiplier (so a 50mm lens looks like an 80mm lens on a 35mm still camera.)
The 5D Mark II gives you 1080p at exactly 30fps and no multiplier since it is full frame and amazing low light performance.
There are many other differences between the two cameras, but these are the main ones that concern me for the moment.
The video format that they produce is H.264 with a 4:2:0 colorspace in a QuickTime MOV wrapper with a 2-channel linear PCM audio track.
All geekery aside, what we’re left with is that both are game changing capable performers for video depending on your needs.
Part 2 will examine what it is like to shoot with these beasties.