AlanF said:
Talys said:
I think that the main reason that most people want more DR is so that they can take a picture that looks like a shadowy block with the sun behind the subject, and then, CSI-style, make actual colors magically appear. Look! Something from nothing!
The problem is, the end result is still a crappy picture that isn't properly illuminated. So actually, it's still nothing
A common example from your hobby of bird photography is when you take a photo of a bird in flight illuminated from the sun above; the top is often perfectly illuminated and the underneath in shadow. It can be nice to lighten the shadows below, which you can do without spoiling the correctly illuminated parts using PS. Your eyes can see the details underneath when your camera can't in one take. The same reasoning applies to other scenes.
Well, that's actually a perfect example that makes my point.
The type of bird in flight that you're likely to get illuminated by the sun above and blacked out below is waterfowl, or another bird low-flying over water. Unless you're at an unusual elevation, it will otherwise be difficult to catch a bird at that sort of angle. For example, hawks and falcon will just too often be too high up for you to catch them from above. You'll rarely get the shot you describe with a songbird.
In this kind of shot,
yes you can improve the photo by lifting the shadows. But it will never be an amazing shot, because the water reflections won't be pretty, and no matter how you raise those shadows, the sun will be at the wrong angle to reflect nicely off the bird's eye and lifting shadows will always result in losing the definition in the plumage (being able to see the feathers) that you'd get if you if the bird were shot earlier or later in the day. Sure, you can fix the water to a degree with a polarizer, but it still won't be as nice as in the right light, and there goes your shutter speed or ISO; what kind of trade is that?
So you get to turn some poor shots into mediocre keepers in post... but if you came at a different time of day, you'd start with much better shots, even before they're touched. Why waste your time with the crappy shots? Just look at where the sun is first, and if it's not where you need it to be, come back another time. I'll be the first one to admit that when I bought my first DSLRs and it didn't cost anything to take pictures (unlike film), I ran out there and took bad shots that I knew wouldn't work out all the time. When I buy a new body or new lens, I do the same thing, because I'm very eager. But it never turns into great photographs.
I think a much better argument would be sports, where your time, lighting, and positioning are much more constrained. But, first, the 6DMkII is not marketed as a sports photography camera, and even if it were so used, I think it has plenty of DR to handle most real-life sports situations.
Oh, DR, the sacred cow. How did it get such status? 
