I recently attended a webinar by a well-known and published author (who shall remain nameless.) I had to give up paying full attention however when he said, regarding raw files:

use the sRGB color space;

use 8-bit images;

using white paper for color balance “in a pinch” is OK “just watch for burn out in your exposure.”

I’m not sure where to start.

If you’re shooting raw, you have a 14-bit range of tones: 16384 shades of RGB and luminosity, and your camera can record -well- past the size of the sRGB color space, so if you switch to sRGB, you’re simply tossing away a huge range of subtleties in your image.

If you switch from 14-bits to 8-bit you’re limiting yourself to the jpg quality range, losing over 16,000 tones in each primary color. You’re also going to introduce banding and clipping during your manipulations in Photoshop.

The purpose of shooting a gray card is the color balance – that the R G, and B values are equal, not that the appearance of gray is “gray.”  The white balance in your camera is about balance, not exposure.  You want something with defined, known values for each primary. A sheet of white paper does not have balanced values (it’s usually overly blue.) That’s why you seldom see “white balance” cards for sale – they are hard to make. A gray balance card for digital is what you want, because the values will be in balance.

My point in writing this is that if you’re going to get into it, you’ll find there is a lot to learn, just as there was a lot to learn with film photography… and even the “pros” often get it wrong.