Information about the Canon EOS M6 Mark II Camera's 30 fps RAW burst feature was limited at the product launch, so I inquired of the man who seems to know everything about the Canon EOS system, Rudy Winston of Canon USA. Here is the very helpful information Rudy shared with me:
RAW burst is a separate line item in the camera’s shooting menu; it’s not one of the listed “Drive” speed choices. So it’s handled like a separate feature, and not just another FPS choice.
As the specs suggest, RAW burst fires at up to 30 fps, and will do so for up to 80 shots in a continuous burst, assuming a fast UHS-II compliant SD card is installed. I’ve tried it with UHS-I cards, and gotten around 50 or so images in a burst.
There’s a separate Menu choice for “Pre-shooting,” which by default is off. If user-enabled, it starts collecting image data **when the shutter button is pressed half-way down,** and then once it’s pressed FULLY to begin shooting, the last 0.5 seconds worth of images before the full press are recorded to the memory card as well. We’ve seen this before, in the video world, and the idea is if waiting for some split-second event to occur (for instance, a bird on a branch, waiting for it to take off in flight), you get the half-second before you actually reacted and fully pressed the shutter button down.
A few other points about RAW burst mode:
The last two points MAY be a matter of it being pre-production… don’t have documentation from Japan to confirm or deny, but thought I’d mention it. At this stage of pre-production, I wouldn't’ be surprised if actual production cameras behave the same way as my sample camera.
Two of the keys that make RAW burst possible are the use of a DIGIC 8 processor, and most importantly, faster read-out speeds of the new 32.5 MP image sensor (while still allowing Dual Pixel CMOS AF to be carried out).
As a practical matter, at least judging from my pre-production sample camera, this feature is VERY sensitive to SD card write speed. A SanDisk UHS-I card, rated at 95 MB/sec, was not sufficient to record anything close to 80 straight images, and the little vertical buffer “scale” on the LCD monitor appeared almost immediately as shooting began. In other words, users should expect to use fast, UHS-II cards to really get the most out of this feature. Fortunately, unlike previous EOS M-series models, the M6 Mark II **is** compatible with UHS-II cards!
Thanks for sharing, Rudy!
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