You guys will probably think I'm weird, but depending on how improved the 70D sensor turns out, I'm thinking about selling my 6D and going to two or three crop bodies. (Downgrading from FF to crop? zomg!)
I love the sensor in the 6D, but it looks like everything else about the 70D is shaping up to be better than it's bigger FF brother. Faster flash sync, better autofocus, higher fps, articulated screen, built-in flash... I can't think of anything on the 6D that is better besides the sensor (don't use GPS). Switching back to APS-C also means cheaper bodies and lenses, which means I can afford more bodies and lenses! (f/1.8 Sigma zoom anybody?)
I would trade some sensor performance for a bit of everything else. It looks like the 70D is going to offer a lot of everything else.
Just don't underestimate the IQ value of those big pixels. You won't get that kind of IQ in a crop body. Even if Canon has made some improvements, and I certainly hope they have (otherwise the 70D IQ will be worse than the 7D IQ), it is unlikely that their 20.2mp APS-C sensor will beat the 6D in terms of IQ. That holds true especially if they have not moved to a new fabrication process...if they stuck with 500nm, then the photodiode area for these pixels will be REALLY SMALL. It would have to be a BSI design in order to make it perform better than the 7D with 500nm transistors (which isn't out of the realm of possibility...just still too early to make the decision to sell a 6D and jump the FF ship just yet, IMO.)
That is exactly where my question earlier in this thread pointed at: does "new sensor" also apply to new tech? If things remain as described here, we are still far off from improved high ISO IQ. So the crucial changes will have to be here. As I have a 5D3 I am very interested how Canon will progress in this during the 5D3's "product cycle". Although it is an excellent camera, I am still keen to see better high ISOs. And what I can guess based on the tech centered threads here a lot of it depends on sensor tech AND processing power via DIGIC upgrades.
Well, new sensor is new tech regardless. It had to be redesigned to achieve the extra 2.2mp, so it IS new technology. New technology does not inherently always mean new fabrication process...which is what a move to 180nm or 90nm would be. I believe the sensor is "new tech", and I believe it will perform well. The big question is will it be competitive...i.e. performing as well as the top competitor chips. If Canon has not moved to a new fabrication process, and has instead chosen to stay with 500nm, then I do not believe this sensor will perform well relative to the competition. It may be only marginally better than the 7D, assuming the weaker CFA of the 1DX/5DIII is applied.
I don't think Canon can remain competitive in the long term if they continue to rely on an ancient fabrication process. I think the 70D will be EXTREMELY telling in that respect, and could provide hints as to the 7D II and "Big Megapixel" camera due next year. If Canon does stick with a 500nm process, then I'll get a 5D III (as it is definitely better than my 7D at this point) and be done with it. If they finally move to 180nm and Cu interconnects, then I'll wait and see what they do with the 7D II.
