Lighting diagram for a product shot

Product work is edges and gradients, not faces: the big soft source comes from behind and above the object so its top planes carry a clean gradient, a white card in front returns just enough to open the shadow side, and a hard strip from the side draws the edge that separates the product from the background. Everything is centimetres: the plan matters less for where things stand than for the argument it records about what each source is for, because on a tabletop every light that is not doing a named job is doing damage.