Thinking about the dynamic range of modern sensors I am concerned that as the size of the "quantum wells" (active piece of silicon on the sensor for one pixel) continue to get smaller and smaller. As the wells get smaller and smaller there is literately not enough physical space for the electrons that determine brightness of the pixel, with out "saturating", which will reduce DR going forward as resolutions continue to rise. This is mostly for 35 mm DSLR cameras as medium format camera "backs" still have fat little "quantum wells" that can hold more than enough electrons.
For example a 14EV would require 2 raised to the 14th power electrons or 16,384 to be contained within the quantum well without overfilling it.. 15 EV would require 2 raised to the 15th power or 32,768 electrons.

Rockwell is dead wrong, in my experience. That's like saying that an old VW beetle is as good as a Ferrari Testrosa, because both can cruise at 60 mph on a straightaway. Let the road be a bit more challenging, and you will immediately feel the difference.

In my case I moved from a Nikon D300 to a D800E. I also use a Canon 5D III professionally at work. The D300 has a dynamic range of 12 EV. The Canon is even less, at 11.7 EV. The D800 comes in at 14.3 EV. The differences are noteworthy in my photographs.

First, let's get something straight: if the scene you are recording has less dynamic range than your camera sensor, it makes no difference at all. It is when the dynamic range of the scene itself gets high that you can tell the men from the boys.

Rockwell says that a good photographer will adjust his camera to the dynamic range of the scene. That's total BS. You can only make a compromise--if the dynamic range of the scene exceeds that of your sensor, you have to decide what to sacrifice--you can either crush the shadows or blow the highlights. Period.

If all you are doing is taking whatever jpeg the camera spits out, then you aren't really going to appreciate higher dynamic range: it is when you get into a good graphics program like PS that you start to appreciate what a couple of extra EV of dynamic range really give you.

I'm going to post some examples. First is a pic I shot a month ago of a stream in the mountains. To retain highlight detail I had to underexpose the rocks. That's the first pic. Then in PS I lifted the shadows. There was plenty of detail in the shadows, and no noise to speak of. That shot would not have worked with either the D300 or the 5D. The tonal values in the shadows would have been blocked up in the D300, and extremely noisy in the 5D.

Just how noisy are Canon shadows compared to Nikon. That's the next frame. This is a direct comparison between the 5D3 and the D800E. I shot identical frames with the two cameras, underexposed 3 EV, and then raised the exposure 3 stops to get a normal exposure--at both ISO 100 and ISO 800. The dynamic range of this particular photo is quite low, so of course I could have exposed normally, but had there been highlights in this picture, or perhaps a bright sky, the ability to expose for the highlights and then raise the shadow values would be invaluable.

If you notice, the Canon is basically noisier at ISO 100 than the Nikon at ISO 800. The Nikon is extremely clean in the shadows at ISO 100--almost as clean as it is exposed normally. Now if I had exposed both normally, you wouldn't see a difference, but with the Canon I would have had no chance to underexpose to preserve highlights and still had clean shadows to work with.

Finally is a pic of a house abandoned five years ago in Fukushima. Again, I was able to expose to preserve highlights, and still keep good shadow tonality and detail.

So that's why I say Rockwell is an amateur if he says that DR makes no difference.

"you have to decide what to sacrifice--you can either crush the shadows or blow the highlights. Period. []

You can also...., gasp..., use the other arrow in the quiver labeled HDR!!
No matter how much DR any camera has, you will eventually run out of DR if you have deep enough shadows and the light source is strong enough.
I could really care less about DR, because my camera can actually do HDR. You can make HDR look as good or as bad as you want. Used properly it's a much more powerful tool than any high DR camera! ;-)
SS

So lets consider some examples for a few cameras.

Hi quality sensors with a full well capacity greater than 32,768 electrons are not unusual.