WHY RETOUCHING RAW VS. JPEG
Raw files provide more image data as jpeg files. They are unprocessed, are used in a much larger color space and therefore give you more options to shift, change and control saturation of colors. They also give you the opportunity to use icc and dng based camera profiles to correct your image data when shot with different lenses and bodies to make them look the same (color-wise).
In general, raw files contain more data, more bit depth and can be compressed as to show more detail in shadows and highlights than a captured jpeg format can.
Shooting raw is associated with being a professional. Within the retouching industry it is basically the same. You want to start with good images, when it comes to the file format. This is as important as the image content, model, lighting, posing, composition,…