Joseph A. Kurkjian
New member
While some could say this isn't totally scientific, it illustrates what happens when the rubber meets the road. It also confirms, unless otherwise dismissed, my feeling that this is more about marketing. We are in agreement.
Hi Andrew:
Well, it wasn't like science was entirely disregarded. The additional two bits were SO transparent in the output files we actually questioned whether or not they existed; in fact, using special S/W tools the presence of the additional two bits was confirmed.
I did notice something interesting about the banding I discussed in my previous post. The "average" intensity change from one band to another seemed to change by approximately 4 counts out of 256 (0-255 range); this worries me more than just a little bit because the band to band transition is such a large change. This banding stuff makes me wonder if Canon is applying internal noise reduction within bands of intensity (below the mid-tones and down to the shadows) in the "real RAW" data before before actually writing what we see as RAW data into user memory (e.g. our CF modules). Maybe the banding is the result of the "internal noise reduction" I'm referring to (perhaps a poor transition from one band of NR to the next, I just don't know).
A real mystery to me is Canon's 1DmkIII white paper Canon claims no improvement in the sensor's DR compared to the 1DmkII (N or non-N version); maybe it is because they can't (i.e. there is no DR improvement at low ISO settings). So, how does a camera achieve better noise performance at the high ISO settings without Canon claiming an improvement in DR at high ISO settings (I mean, Madison Avenue would never miss an opportunity like this, right)? I'm guessing that Canon isn't claiming an increase in high ISO DR because again, they can't; they couldn't claim an improvement in in the sensor's DR if all they are doing is using some of that Dual Digic III horsepower to implement crude noise reduction techniques in the dark part of the image at the expense of shadow detail and maybe creation of these bands that I see when you have a smooth transition from shadows on up to the mid-tones. An Imatest DR analysis at high ISO settings will probably show an increase in DR because of how DR is measured by that tool. Maybe Canon is content to letting the user community "think" there is an improvement in high ISO DR without making a false claim about the sensor (I just don't know).
Oh well, the heck with it, I'm more interested in taking pictures and all this mental anguish over the technical aspects of cameras (ones I own and the 1DmkIII, one I would like to buy) doesn't help my composition or catching a potentially nice scene out of the corner of my eye. I'm ten days away from a three week photography trip and still confirming fifty million reservations - I'm back to work!
Regards,
Joe Kurkjian