1. White balance is a type of processing applied to an image after the sensor has recorded it. Thus, for RAW images, which are essentially unprocessed images from the camera sensor, there is no camera setting for it; a white balance setting is applied when you convert the RAW image to another format (such as JPEG).

2. It doesn’t apply at all to black and white images. Traditionally, any tints you get in black and white images are related to the particular paper and chemistry you used to make your print; not even how you develop the film makes any difference.

3. There’s no “perfectly correct” white balance for any shot. You can find a setting that seems quite realistic, but then again, given that you’re really producing just a flat image possibly representing a real situation anyway, there’s no harm in playing about with white balance just as you’d play with any other settings on the camera. I once did some very pleasing stuff by using outdoor colour film with fairly long exposures in a dimly-lit bar; it came out very “red,” but very pleasing.