My review provides a detailed discussion of the book's contents but if you have a train to catch, here's my verdict in a nutshell. Frost's is as good a book on filters as you are likely to find, with one caveat. The digital revolution has made large sections of this book obsolete, and it is not such a long book to begin with.
Simply put, if you are a digital camera user like me, you'll find some of the material of no use. Other sections, while not necessarily useless, will describe effects which are now routinely achieved using image processing software. Luckily, there remain valuable sections on filters such as polarizers or ND grads which are still essential for digital photographers.
PS. If you are a film photographer with an interest in using filters, this book is a treasure trove of information - but then you probably know it all already, an old hand that you are.
I can imagine just how invaluable this book would have been in the nineties or in the early noughties, when digital cameras were a fascinating and expensive glimpse into the future. Lee Frost is an acclaimed landscape photographer, and he had poured into this slim book a wealth of information about the use of filters for film photography. However, now that film is quickly becoming a fascinating and expensive glimpse into the past, unnervingly long passages in the book have become dated or even obsolete. I mention this because for a book first published in 2002 and reprinted regularly ever since, it is disappointing to find that the author has chosen to ignore the technological advances and fails to acknowledge even the most basic requirements of digital photographers. For instance, if you would like to know how the cropped sensors of many modern SLR cameras affect the performance of a particular filter or filter system, Frost's not gonna tell ya (though he probably oughta).
This visually attractive book has been divided into a number of short sections devoted to different filter types, each illustrated with beautiful, high quality images.
1. Choosing a filter system
Describes the different filter types (screw-on or slide-in) and discusses the size and application of the major systems and brands (Cokin, Hitech, Lee, etc.). This section is highly useful, even if a note on cropped sensor cameras would be in order to make this section complete.
2. Polarizing filters
3. Graduated filters
A very useful introduction to the two essential tools of landscape photography.
4. Colour-balancing filters
This section is a mixed bunch. Where it discusses colour temperature and compensation (pages 53-59), it is only useful insofar as it effectively explains in simple terms what colour temperature is and why it matters. However, the techniques which are used to control and use colour temperature are different in digital cameras (each film type has its fixed colour temperature range that yields natural-looking images; in digital cameras, where the colour temperature is a matter of settings, no filters are needed).
Still, even if you are a digital camera user you will need to have an understanding of this phenomenon in order to figure out which settings will help achieve your intended result - in this sense, this section is worth a read.
Later on in the section (pages 60-67), correction filters are discussed (warm-up, cool-down, colour inversion, etc.). Again, when processing RAW files in your computer such modifications can be made at your leisure with no need for actual filters. Still, the pictures are pretty and inspirational.
Colour compensating filters (pages 68-74) are an answer to a problem long solved - just enter the White Balance setting in your camera menu or RAW processing software. Indeed, more often than not your digital camera will competently take care of that for you (Auto-WB). Only of use to film photographers.
5. Neutral-density filters
Here we get back into the timelessly useful territory of ND filters. These (i.e. non-graduated ND filters) are your ticket to those milky waterfall shots. The section is full of solid useful stuff and suggests some other creative uses for ND filters (pages 77-82).
6. Filters for black-and-white photography
Again, the issue of technological obsolescence re-emerges here but with no experience in B