I think we have an emerging winner, and I guess it shouldn't be a surprise as folks shoot FF for DoF and low light capabilities after all. The former is determined by glass, the latter by sensor performance / noise reduction. You really don't need a FF solution otherwise truth told.
Aside from a shift of the CFA itself, which I know other folks in the smartphone business have looked at but has drawbacks in color accuracy (obviously not ideal for dedicated camera platforms), or, AI/machine learning application, really the only place for Canon to go is BSI and stacked CMOS or Global Shutter. The trouble with the latter is dynamic range loss that folks thus far who have done Global Shutter have contended with, even though it's rumored that's what the R1 will be Global Shutter, which the 2nd contender here is Dynamic range, again another non-surprise as folks shoot larger formats for image quality.
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Since the latest Canon's are dual-gain, there's not much else Canon can do for DR, for the moment, other than what they already have, providing a more HDR SOOC format, HEIF, which isn't well adopted. RAW shooters obviously don't benefit, but, HEIF itself is necessary as the existing DR is "wasted" on JPEG formats when displayed on most electronic viewing formats.
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I am curious what Canon's latest DIGIC has in store for us though. It hasn't been discussed, however, it's a foregone conclusion the R1 will need a new one to handle faster readout of higher megapixels. Battery life is another hiccup of mirrorless vs DSLRs with constant EVFs or LCDs running in addition to constant sensor readout for AF purposes. Hybrid core DIGIC implementation and more energy efficient display panel/EVFs can help, but, DSLRs will always have the advantage. Can more efficiency and better battery tech close the gap? Me thinks no. I do think there is some blood in this turnip though.
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Interesting results of the poll, thus far. Glad I ran the thing.
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The rumor of the R1 being global shutter though, I'm starting to think it's going to be an A1/Z9, that is stacked CMOS though, loosing dynamic range for faster readout doesn't seem like a loss tenable for the target audience.
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Also, curious to see what Canon does for the lower end upcoming models; will they pull forward DIGIC8 or DIGICX with updated software ala M50 Mark II for cost, or, will they give it bleeding edge DIGIC chips for energy efficiency and size reduction? The lower end of the R spectrum is all about size, cost. I'm thinking they'll do the former, DIGIC8 or DIGICX with updated firmware as the lower end is definitely cost-effective, which newer DIGICs aren't.
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Autofocus is a known Canon is addressing with the R3 and thus R1, so I won't speak to it other than faster readouts and better software are going to be better AF. It's safe to say your R1 and R3 will be better than your R5 and R6. How much? We'll find out in a bit. Whatever the R3 does, the R1 will do, and maybe then some.
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I gather we'll see some of our wants met (better ISO), and others not (dynamic range, battery life, depending which model).
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I'm really curious if Canon will do a A7C-like competitor. They have the M though which is even smaller, even more cost effective, so dunno if that's a niche Canon needs to attack.
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The R makes for a fierce webcam btw, it wouldn't surprise me if the upcoming low end R is somewhat webcam focused, in addition to being a standalone camera.
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Lastly, although the rumor mill has been dead about a R5R (super res monster), I'm certain from Canon's previous efforts (125MP FF sensor which they've relegated to security cam purposes) one is in the making. Again, like the R1, it's probably waiting on a more capable DIGIC processor to go with that much data handling, and like the R1, waiting for stacked CMOS implementation as that much data needs a faster readout to be effective in photographic/video documentation use cases other then just security monitoring; 125MP is alot of rolling shutter without a faster readout of stacked CMOS.