The Canon Cinema EOS C300 Has a 4K Sensor but Outputs a Maximum of 1080P
The just-announced Canon Cinema EOS C300 has a 4K* sensor. But yes, there's an asterisk there, and it turns out the Super35 CMOS sensor's native resolution of 3840x2160 (which is exactly double that of 1080P's 1920x1080 resolution) isn't a "traditional" 4K, and the camera outputs at 1080P. It reportedly has 1920 x 1080 pixels for red and blue, and 1920 x 2160 pixels for green. Here's the deal from DV Info:
The 8.3 megapixel Super-35 sensor in the C300 is a new CMOS design by Canon. It is not borrowed or re-engineered from the still photography side of the company; instead it has been created “from the ground up” and dedicated specifically to digital cinema applications. The sensor has a resolution of 2,160 pixels tall by 3,840 pixels wide, which qualifies as native 4K. Canon claims that rolling shutter skew is greatly reduced in this sensor relative to current HD-DSLR camera models. Also, each frame can be scanned by the Digic DV III processor more quickly compared to an HD-DSLR, such as the 21 megapixel CMOS sensor in the Canon EOS 5D Mk. II, which has 2.5 times as many pixels as the C300.
Canon says that their Digic DV III processor reads this new sensor differently; it does not use the line-skipping method found in high-res HD-DSLR sensors. Instead, every four pixels (two green, one red, and one blue) are sampled for each final output pixel. In other words, color is assembled the same way as a traditional three-chip sensor block… two megapixels of red, two megapixels of blue and four megapixels of green (twice as much green as red or blue, since green carries the luminance info). Each primary color sampling off of the sensor is native 1920×1080, each color value alone is equal to the final output resolution. Canon claims that the processed signal has 1,000 lines of TV resolution, and the moire, diagonal line stair-stepping and other artifacts are greatly reduced in this chip compared to HD-DSLR cameras.
From Engadget's live blog, here's the color configuration:
Canon claims the camera resolves 1,000 TV lines. According to the Single Chip Camera Evaluation, which measured "line pairs," this puts the C300 squarely in range of the Sony F3 (its closest competitor, both price- and specs-wise) and short of a true 4K camera. This is not to engender a "4K doesn't matter!" comment thread, but since they're talking resolution, let's see how the C300 should stack up! When looking at this chart, multiply all numbers by two ("line pairs" are just that -- measurements of two lines, as opposed to Canon's measurement of one):
The chart suggests the RED ONE resolves 2080 TV lines, which sets the benchmark for 4K cameras (one can only assume the 5K EPIC is slightly higher). On the other hand, I'm a stickler for color rendition, and Canon is obviously shooting for that as a selling point, which to me is not RED's strong suit despite the RAW workflow. Canon has always been known for great skin tones, and I'm looking forward to seeing how the C300 handles color; we'll see once official video is released. Much more to come, and not just about the Canon offering -- RED's SCARLET announcement is coming right up.