PureClassA said:
Ok now I'm even more perplex. The blog mentions "taking advantage of the full 14 stops of DR the sensor IS CAPABLE of" So now I gotta ask....if the sensor is CAPABLE of it....what the hell are we talking about with bad DR? Granted the base Canon firmware doesn't allow for dual ISO HDR single shooting... but it seems the sensor CAN produce it given the right tweak. I guess I'm wondering if the DR issue is really a sensor issue...or a Canon firmware issue? I need people way better versed on this than I am to help me. Glad ya'll are here LOL
Most SENSORs these days are not that noisy in the grand scheme of things. If Roger Clark's data is anything to go by, Canon sensor DR is anywhere from 14.3 to 15.7 stops. Canon's most significant problem is the introduction of noise from downstream (off-die) electronics. Primarily, read noise introduced by their high frequency ADC units, of which there are four, eight or sixteen separate units on the PCB board, between the sensor and the DIGIC processor(s). It's that electronics that adds some quantity of noise to every single image read off the sensor.
If the sensor starts out with 14-15 stops of DR, it's the introduction of read noise from other non-sensor electronics that is basically "eating away" at dynamic range. Canon's off-die electronics, given that their sensors usually have around 11 stops of DR, are apparently reducing dynamic range by 3-4 stops! Canon's problem isn't necessarily their sensors (not explicitly)...it's the way they read the sensor signal out. The solution to Canon's problem is to reduce the operating frequency of readout electronics, and reduce trace paths along which pixel data is transferrred. The best way to do that IS to improve their sensors...by moving ADC units onto the sensor die, by increasing ADC parallelism, and by employing other technologies allowed by CMOS sensor designs to increase Q.E. and reduce sources of additional noise (outside of the amplifiers in each pixel themselves.)
That's what Sony did...they moved all the readout electronics onto the sensor, hyperparallelized the ADC units (one per column), and employed a number of other techniques to reduce noise futher (i.e. moving high frequency components, such as the clock, to remote areas of the die so they don't risk injecting additional noise into the pixel data as it's read out, use of digital CDS, use of per-column tuning in each ADC unit to eliminate vertical banding, etc.)