In this FAQ a number of sources fill in the blanks for the 1D X Mark II’s impressive video capabilities, especially Ebrahim (thanks) on the EOSHD Forum via his official Canon contacts.
Why MJPEG and not H.264? What are the crop factors in 4K mode and 120fps slow-mo? Is Dual Pixel AF the next generation or the same as the 70D?
Read on to find out.
Why MJPEG and at what bitrates?
According to Ebrahim’s Canon source the camera’s weather sealed body and lack of fan excluded the use of the more complex XF / H.264 codec of the C300 Mark II. As the 1D X Mark II is built for absolute reliability, overheating must be avoided. If you need 4K H.264 but are willing to suffer 3 minute time limits and regular problems with overheating during a shoot consider the Nikon D5.
The downside of MJPEG is that due to the ‘simple’ encoding it is inefficient. File sizes are enormous but image quality is maintained.
The bitrate for 4K 24/25/30p is 500Mbit/s like the 1D C. The bitrate for 4K 60p is 800Mbit/s. At that data rate a 64GB card fills up in 10 minutes, so 60fps is better kept as an option for short bursts where a mild slow-mo effect will be applied in post.
Like the Nikon D5 the Canon 1D X Mark II records 4K from a cropped window of the 20MP full frame sensor. Unlike the Nikon D5, the 4K recorded is of the higher resolution digital cinema variety at 4096 pixels wide therefore the crop is a little less severe than the 1.5x Super 35mm window on that camera. The 1D C is a 1.3x crop or APS-H although I have heard it referred to as slightly wider than that or a 1.25x crop whereas the 1D X Mark II is a slightly narrower 1.4x crop due to the higher megapixel count of the 20MP sensor.
There is no full frame 4K option and the camera isn’t Speed Booster compatible.
The Full HD resolutions are full frame, since they’re pixel-binned. However this is not a primitive line-skipping technique, but a more advanced pixel mix which Canon say should reduce moire and aliasing to a minimum and provide a high resolution. I expect the 1080p quality of this camera to be a step up from the 5D Mark III in terms of sharpness, with as little moire.
Is 120fps a crop and what’s the final format?
120fps and 100fps on the 1D X Mark II is full frame with no crop as it is pixel binned. It is not recorded continuously with audio to a 120fps file, rather it is conformed in-camera and there’s a slow-mo menu option where you can select the conformed frame rate.
Is the HDMI output 4K?
Canon say the purpose of this on the 1D X Mark II is for recording lower resolution proxies for editing rather than bypassing the 4K codec on the camera. Therefore they have limited the HDMI output to 1080p and enabled simultaneous internal 4K recording whilst outputting this 1080p signal over HDMI.
Personally I would have preferred to have seen a 4K output on this camera to bypass the large file sizes of MJPEG and record 4K straight to ProRes 422 LT for a file size saving of approximately 25% with no loss of quality. This would have also given a file which could be edited smoothly.
Is Dual Pixel AF improved over the 70D?
Here’s what Ebrahim had to say about this on the forum:
“Dual-pixel AF here is vastly improved. Its our first FF size image sensor to incorporate the technology. Over the 70D, the 1DXII offers full control over auto-focus behavior in terms of shifting speed (10 increments, 1 being slowest and suitable for on-film use, while 10 is much faster and suitable for acquiring focus prior to recording), the speed of DPAF can be set separately for stills and video modes.”
“In video-modes, AF can be set to manual subject choice (using the newly developed touchscreen) or face-tracking and the system will accurately follow the subject smoothly with zero failure rate as the AF is using more than 16 million points in DPAF as opposed to a few on-chip points .”
“Dual-pixel auto-focus works in all video modes including 4K capture modes.”
Unlike contrast detect based AF tracking as featured on the Panasonic GH4 I have found Dual Pixel AF to be a fantastic feature, very reliable with no hunting and a nice cinematic aesthetic quality to it. It’s almost like having a professional focus puller in a tiny box – but not quite. In my view though it is definately the future and along with the touch screen functionality on the 1D X Mark II will make for some very convenient moments. You can see Dan Chung’s first demonstration of it below:
What advantages does the Cinema EOS 1D C maintain over the 1D X Mark II for video capture?
As a 1D C owner myself I am on the fence about whether to swap.
The 1D C uses a wider field of view from an 18MP sensor rather than crop the same resolution of 4K from a more crowded 20MP sensor.
It shoots at a higher maximum ISO in 4K of 25,600 whereas the 1D X Mark II caps this to 12,800.
The 1D C offers better image quality for 24p 4K shooting as it includes Canon LOG, which is vital for maximising the amount of dynamic range stored in the 8bit files. This feature is also useful for matching the 1D C precisely to other Cinema EOS camera such as the C100 Mark II and C300 Mark II on a multi-camera shoot. It is a fantastic LOG format to colour correct and grade with an easy gamma curve to handle and superb colour performance.
The 1D X Mark II does not add basic features like peaking and zebras so the main upgrades remain AF related and the higher frame rates.
The 1D C records 4K to cheaper Compact Flash cards whereas the 1D X Mark II’s 4K mode requires CFast 2.0.
The 1D C does not have the 29 minute 59 seconds recording limit of the 1D X Mark II, although it does span long recordings over multiple files.
How does the new sensor differ to the one in the 1D X and 1D C?
“The sensor uses an entirely new on-chip ADC design, as well as micro-lens gapless design. The new chip offers marked improvement over the predecessor in high-iso performance and dynamic range that’s applicable to still images and video mode. The sensor was designed for speed in-mind therefore allowed the 4k60/HD120 plus vastly improved rolling shutter performance on the video side.”
“I can definitely confirm the 4K video image off the new sensor is the highest quality video of any Canon DSLR camera, in terms of resolution, dynamic range, lack of compression artefacts, and striking lowlight ability. The image reproaches that of current highest-end cinema cameras in a DSLR body, with AF and phenomenal stills performance. And a major point is that the 1DXII quality allows it to go places even the Cx00 cameras simply cannot due to the [weather sealed] body.”