I just finished reading (and I intend to re-read) a wonderful book called "Edge of Darkness" by Barry Thornton. It is not a reference book where you can look up specific developers - I'm sure the book mentioned above will fit that purpose much better. I'm mentioning it here because, though it does have lots of information about how various developers and ingredients in developers work, it has much more. It discusses how the eye sees, how the brain interprets, what components make up the quality which we generally call "sharpness", and it draws from the author's personal history to relate all these things in a very personal way. I think it is a marvellous book. Since it does include much about the topic at hand here, I thought I would like to share it. Barry Thornton's web site address is: http://www.barrythornton.com(posted 8095 days ago)-Ollie http://www.web-graphics.com/steinerphoto