I don't understand Picture Styles. The contrast, saturation, and color are all 0, all styles. But the sharpness settings change from one style to another.
I read that Standard has more sharpening than Faithful, 3 and 0 respectively. This makes sense.
I read that Standard is more saturated than Faithful, both are 0. This makes no sense.
If the styles have hidden values, and the 0 means "default" for each style, then why is sharpening a non-zero value?
The settings in each style is meant as a starting point, you modify the settings to your personal taste. The idea behind having Landscape, Portrait etc is just a convenient place to store each setup so that you choose a preset style quickly without having to change 4 settings each time. There are no hidden values.
It looks far more complicated than it is. Personally I never use them because I shoot in raw.
I will have to withdraw what I said about "no hidden settings" now that I've studied it a bit more.
I have noticed that in DPP 4 when you change the style even though the sliders do not change there is quite a drastic change to the histogram so something is certainly happening.
I played with Canons (very crude) picture style editor program and can see that you can change Hue, saturation and luminance together with selective colour changes and curves so changing to one of the preset styles could be doing almost anything, but whatever it is Canon isn't telling us.
True there is no picture style "baked in" when you use raw. But you really do have to pick one from the list - DPP or ACR, neither of which includes "no picture style" - when you process from raw to ANYTHING else. Do you never make JPGs or TIFs?
"It's not meaningless if you use DPP."
"...you really do have to pick one from the list"
You have to pick one for your computer. Not the Raw file. You can not view a Raw file as is, so a viewable copy is made for you by the conversion process. It is meaningless to the Raw file. Noting is changed, nothing is altered. You can't even save the Picture Style in your Raw after you view it. Only the viewable copy, likely a jpg, maintains that info.
Don't like the Picture Style, change it as many times as you wish. Still the Raw file is unaffected.