Spotone and similar products are not meant for the same purpose as Marshall's photo oils. The former are meant for spotting out small imperfections like dust spots, small scratch marks, and the like. Marshalls photo oils are meant to hand color the print. Two different applications. Here's an example of something I did with a similar product. It's not a great photo, to be sure. As a proof of concept thing, it illustrates the point that it can be done.