Tone Control in Photography

There are many factors that can influence the tonal quality of your photograph, from the shooting stage right through to post production of the image in both film and digital. A rich range of tones in both colour and black and white photography is very important in the success of the image.
The obvious factors that would influence the tones of an image during the shooting process is the lighting as well as the subject reflectance. The type of lighting the photographer uses, whether it is hard lighting, or soft lighting and the size of a light source also affect the tonal range of a scene, the colour quality of the light will also affect the tones of an image. The subject brightness range is important; this can be defined as the distinction in luminance from the darkest to lightest areas of the image. The photographer would want to get a good range of tones from light to dark without losing details in the lightest and darkest areas of the image. A black subject in comparison to a white subject will have different SBR.
Other factors relevant to the tonal quality of an image during the shooting stage includes the use of the different filters in film and digital, for example a polarizing filter will cut out reflections, but will increase vibrancy and this expands tonal range, where a diffuser would do the opposite because it lessens the contrast.
Also it is very important to shoot in digital RAW format, as opposed to Jpeg, because the bit depth used to encode an image also has quite an influence on the tones of a picture. 8 bit (Jpeg) records up to 256 levels of information, where 16 bit (RAW) records up to 65,536 discrete levels of information, the difference cannot even be compared.
Exposure would of course have an effect on the tonal quality of an image because if you over or underexpose an image it will be either to light or too dark and affect the overall tones of the final image, so exposure accuracy is very important.
Other things to look at would be...