I had bought there a few times the book of Dennis Thomas; "FLASH CANON SYSTEM" and I was very happy because he gave valuable information about the use of Flash CANON. So I hesitated to buy a second book on the same subject and to rave reviews on AMAZON I started and I have no regrets: this book is in my opinion what is the best on the subject: there describes the use of a flash in every possible situation and it goes much further especially considering all you can do with a flash system. It caters to the course material CANON owners but not only: While all the examples are made with Canon flashes but apart from handling all the flash itself is transferable to any other brand. In short, a book that reads almost like a novel, and where there are a host of interesting ideas