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Agree with Peter. The best gauge for YOUR color workflow are not downloaded test files it is the files coming out of your camera. But what you need to make head/tails of what comes out of the camera AND keep it consistent is a consistent process control baseline.
Custom WB with the gray card and having it in test shots FROM YOUR CAMERA you view on monitor and print will tell you more objectively what what the monitor and printer are doing differently to the SOOC image. Also useful in test shots is a MacBeth color chart. It's easier to compare color shifts on it objectively than from content which changes subject-to-subject.
These shots illustrate the process controls I use. My process control targets consist of a plain 8 x 10 Kodak Gray card used for setting Custom WB and another with a MacBeth ColorChecker on it to better see how colors shift on the monitor and printer gamuts.
Here's an example of setting Custom WB, which is the first step in the workflow. This is a shot of the gray card taken with Daylight WB setting on camera with flash illumination. The flash is a higher color temp so from the Daylight baseline the card is recorded as blue:
Here's a shot of the card after using that frame for setting Custom WB:
The camera shifts it's color balance from the Daylight baseline to one that makes the card's RGB values equal and "technically" neutral on all files straight out of camera (SOOC). What I'm doing by setting Custom WB is "trusting" the camera's baseline as being neutral. Because all the color is known to be neutral SOOC I don't need to fiddle with it by eye on the monitor to try to fix it.
Once WB is "normalized" in whatever lighting I'm using my next concern is exposure. Can the sensor record the entire scene or not? To determine that you much "lock down" exposure on one end of the scale or the other, highlights or shadows, then examine the other end in a test shot. Since highlight detail is usually more critical than shadow detail I make nearly shots with solid white highlights below clipping. For lack of a better gauge of clipping I use the camera playback. I use a white towel as a proxy to help me gauge highlight exposure in the playback warning. Once I get exposure adjusted for the highlight detail I use a black one as a proxy for the darkest content I'm likely to include in a scene.
I also put a MacBeth color checker on the gray card. I don't make any decisions about color with it at capture, its there to help me see the way the color differs on screen vs. printer when I "soft proof" and print the file.
Do I always set-up that way? Yes, when circumstances allows because I find the 1-2 minutes spent up front getting the color neutral SOOC and capturing detail in the highlights saves a lot of time and hassle in the following steps of the workflow.
I always have flash available outdoors (two of them) to handle lighting that exceeds the range of the sensor. The flash can't fit everything to the sensor with normal detail but it can "fix" the foreground. For example here's a shot in cross light, ambient only, exposed for highlight detail in the solid whites:
Here's the same ambient lighting with flash added to "normalize" the tonal range in the foreground:
Note how the background is the same (underexposed) in the flash shot because the scene contrast exceeds sensor range, but since the more important detail is in the now correctly exposed foreground the shot seems more "normal".
Here's a backlit portrait with the same strategy and gear:
The background in that shot is just as underexposed as in the flash shot above, but because it's a sunlit river behind her the underexposure isn't noticed. That illustrates that how you select backgrounds that will make some results look more "normal" than others.
I had to do very little PP in that shot because the color balance was neutral SOOC because I'd set CustomWB and she was recorded with normal looking tonal range because I exposed the sunny parts of the white jacket under clipping and then raised the flash on my bracket to match PERCEPTUALLY. Not exactly match the strength of the sun, but just a bit less to preserve the ambience.
The point of all of this? An ounce of prevention SOOC is better than a pound of cure in Photoshop.
Getting it as close to nominal in the camera saves time and hassles in post processing AND give you a trusted baseline from which to spot problems with monitor or printing. That shot of my wife looked the same on the SOOC file on the monitor (calibrated) and print (reasonably accurate profile) because on both the white jacket looked neutral (no color casts) and the images had similar "normal" ranges of detail (no blown highlight or blocked shadows).
The look of the color in an image can be manipulated with Styles. The shot below shows what happens when different styles are applied to a RAW file. Custom WB was set with a gray card before shooting the target. Styles were changed in post processing:
Note that the white>gray>black tones stay exactly the same on the MacBeth chart. What the styles change is the saturation and hues of the colors. Why would you do that in a photo? A Ferrari would look better in Landscape mode, the skin in a portrait better with the other three less saturated modes. The patches on the card are selected to be similar to caucasian and brown skin, blue sky, red cars, green grass, etc. It's easier to see the changes objectively on the chart by comparison than if you simply compared a portraits without the target.
When I do posed studio shots I have the subject hold the target after setting Custom WB and adjusting the exposure. Then I'll try different styles and make other selective tweeks in ACR as shown below BY COMPARISON with the SOOC "Neutral" style baseline I use all the time. Sometimes the SOOC Neutral shot winds up looking the best, other times changing the style and making the colors "pop" more looks better.
That's where having a well calibrated monitor is important, so the decisions you make by eye will wind up looking the same way when printed. Once I get that card shot adjusted to taste by eye I copy the adjustments into the other RAW files and they get adjusted similarly automatically. From that point on as I edit all the other I don't need to worry about the color. That's where the up front step of setting Custom WB and carefully controlling exposure and tonal range pays huge dividends.
The best part? If you use the calibration device correctly and select the correct profile for the printer/paper/ink you are using those aspects of color management happen correctly automatically. If they don't? Your trusted SOOC Custom WB from Gray Card process control baseline will help you determine where the problem is and how to fix it.