Ordered this for my photographer-husband who had recently attended a seminar in which Bryan Peterson was a presenter on the subject of understanding and using your flash. He anticipated the book would cover much more than just the presentations at the seminar.Though my beloved appreciated Peterson at the seminar, he loves the book, telling me that Peterson says some of the same things (expected) but "in a different way and from a different perspective" than he did in the seminar. Reading the book he has learned some things he did not know, come to understand some things he has not pursued with his flash, and has not felt like the seminar was just a replay of the book's contents. He is really enjoying, being challenged by the content, learning as he reads and making additional application. He has commented that Peterson is a good writer.Though this may come off to some readers as a review of the seminar vs the book, it is not. The comparison actually reveals that Bryan Peterson is skilled in his subject and a very good teacher. When one is able to communicate a concept using different examples and from different perspectives, he broadens the follower's comprehension of a subject. Peterson speaks effectively to those at differing skill levels. I know he rates the book and author as 5 stars.