Originally posted by Winder The comparisons really only prove that current ASP-C sensors are as good as 5-6 year old FF sensors.
Until we have a new FF from one of the big 3 we will not how much a difference there really is.
If Sony rolled out their 16MP sensor for the mid-level cameras like the A55/D7000/K-5 then it is a pretty safe bet that the 24MP sensor that is going into their A77 and probably the Nikon D400 is a step above in overall performance. I think it is also safe to assume that the 32MP+/- FF sensor going into the A920 or A99 is also going to be a really good sensor.
Exactly.
There is a continuum of quality, but smaller sensors (due to lesser costs and higher consumer product turnover) allows for faster development.
FF takes BIG leaps less often, and APS-C and M43 and P&S take smaller leaps more often.
IQ is partially subjective and partially non. DR is is non. Resolution input is non. Sharpness can be subjective because, frankly, the scales used defy the user's eye and the digital noise vs. sharpness tradeoff is a constant negotiation. Frankly, all manufacturers make very sharp glass at center, and only more extreme designs (WA for example) display some flaws, which is inevitable in optics. Every manufacturer has a dud lens or two.
Sensor IQ is a continuum. Smaller sensors will reach a ceiling on advances faster than larger sensors. M43 will get there 1-2 generations before APS-C, and the latter will get there 2-3 generations before FF, and on to MF, etc.
This is why the Sony NEX mount can handle and FF sensor and the Pentax 645D can handle a larger sensor as well. They are future-proofing for the day when incremental quality improvements can only be made when the sensor is larger. Getting there will depend more on economics than anything else.
The Nikon D400 and D800 will be interesting cameras, for sure.