Yeah, shooting something like a Passport Colorchecker is definitely the best. Since in the JPEG stored in the RAW file that's presented by viewers (viewer demosaicing is too slow,) I like to have the correct WB for ease of review. So...just a difference in priorities.
It's funny how the limitations on some settings don't make any sense. Nikon has a setting called Flash Shutter Speed which defines (I think,) in A and P mode, the crossover point from fill flash to key light. So if it's set to 1/60s, the camera will set ambient exposure while lighting conditions call for a shutter of 1/60s or faster. In this case, the flash acts as a fill light. But if the lighting calls for a slower shutter speed, the shutter stays at 1/60s, underexposing the image. At this point, the flash becomes the key light. Seems straightforward enough...except for the fact that you can't set an FSS faster than 1/60s. I don't understand that limit. I tried hard over the course of many emails with Nikon to get them to explain the idea behind this setting, but to no avail. I can't see any reason why a setting of 1/120s would be a problem.The 1Ds3 has options for minimum and maximum shutterspeed, although for some reason they set the fastest minimum speed to 1/60th, and the lowest maximum speed to to 1/250th (I must admit that I never really understood that decision -- possibly a mechanism to stop people thinking they had a broken camera because they mis-set those settings). To be honest, I never really use safety shift / auto ISO - I'm just not getting big enough variations in lighting to warrent it.
However, there are other seemingly strange limitations that have valid reasons, such as Nikon's reduced max-aperture limits when using flash with P mode and elevated ISO values (as ISO goes up, the max aperture that P mode uses gets smaller.) That's simply a flash power thing. Many people don't understand why their cameras refuse to meter in some low-light conditions...not realizing that they gone past the 0EV metering limit. So I'm pretty sure there's a sound reason for why Canon and Nikon have such limitations (at least that's what I tell myself )
Well Pentax cameras have an actual shooting mode, TAv, that does just that so someone must think it's a good idea. It's really nothing more than switching which parameter the camera controls in auto modes. In Av and Tv modes you also control ISO, so you always have two settings under your control. TAv mode (and manual + Auto-ISO on a Nikon) simply puts ISO under the camera's control while you control aperture and shutter. The Pentax guys seem to like it for sports.This seems somewhat counter-productive to me - if I'm wanting manual control then I wouldn't want the camera changing ISO willy-nilly on me - that would be a disaster for a lot of things that I shoot. I take what you mean about the metering indication (1Ds3 has 3 stops anyway), but again, I don't think I'd want a centred meter because it wouldn't give me a true indication of where things are going to expose - especially when I have up to 7 spot-metered points graphed on the meter.
Ah, but it's great for shots where you're capturing the reflection of the scene in a lake, where you want the reflection to have the same weight as the scene...just like Steichen's The Pond - Moonlight (which sold for 2.6 million bucks ) But really, it's just like any other indicator on the camera. It's just a piece of information to use as you see fit. The balance point may be 4 EV, and knowing that you want, for example, a 2EV difference, you grab a 2EV GND. The thing to note is that it's a quick method to get some valuable information.With regards to using it in conjunction with GNDs, good theory, but in practice, I'd never do it this way -- IMO opinion trying to balance a shot this way is flawed because it breaks the rules of local contrast; for example, if you have a scene with a sunset skyline - and a "balanced" foreground - then one would naturally expect the skyline (being incident light) to be brighter - when it's at the same level as the foreground, it just doesn't look right. Ironically, I find that 99 times out of 100, it's a 3-Stop thet I need anyway (seems to be the most common difference between incident light and reflected light coming from shadow detail that I want to protect).
And I think we can also agree that we really like our cameras!Knew we'd find common ground eventually