I need a tool for automating knockouts of a large image database, mostly of subjects photographed against monochrome backgrounds. I have not used any of the third party plugins for Photoshop and am wondering which might be best. Many images have fine detail such as hair and even against a solid background there are lighting variations and shadows in some cases. Since there are several thousand images in my database it's imperative that I find an efficient tool, or I will need to rethink the in-progress design of a web site. As I mentioned, the images are mostly against solid backgrounds but in some cases the subject and background color/contrast are not really pronounced. Any shared experience appreciated.