Books:

Photoshop techniques: We are talking about digital work, after all.

There are many books promising to turn you into a Photoshop guru. Unfortunately, most are either disorganized, filled with fluff, or lack needed detail. The references below are all filled with useful and practical information, presented in a format that helps you find what you need.

Real World Photoshop CS4 for Photographers, Chavez, and Blatner, 2008. This is by far the best overall reference to everything Photoshop related. If you do much work at all in Photoshop, this book is essential. Real World Photoshop gives extensive advice and examples on all aspects of Photoshop, from editing to printing to the web. The CS4 edition focuses on the needs of digital photographers. The emphasis is on practicality. There are many ways to accomplish any given task with Photoshop; Real World Photoshop helps you choose the best and most efficient. New features Adobe added in CS4 are described effectively with guidance on their use on actual images.
Adobe Photoshop CS4 for Photographers, Evening, 2008. This book is based around sets of pictures, showing how to edit them. Photoshop for Photographers is best used to make already good images better. It complements Real World Photoshop very well, but does not serve as a replacement. If you can, get both books — your images will thank you. As always, the most important and useful new features for a photographer are highlighted, explained, and made accessible.
Adobe Photoshop CS4 Classroom in a Book, Adobe Creative Team, 2008. This book and the included CD of exercises go through a series of lessons that cover all the fundamental Photoshop techniques. It has comprehensive coverage of the fundamental Photoshop features including layers and masking, presenting images on the web, retouching, and simply navigating the Photoshop user interface. The latest CS4 goodies are also covered, although a few of the newer lessons are less well polished than the rest. Overall, the web tutorials are among the best we have seen — most web sites displaying photos could benefit greatly from the information in this book. The step-by-step tutorials bring you up to a proficient level in a minimum of time.
Photoshop Restoration and Retouching, 3rd Edition, Eismann and Simmons, 2006. This book assumes you are already well versed in basic Photoshop techniques. It is the best reference I know of on how to restore scans of old, faded, or damaged photos. Most of the techniques work equally well on imperfect images from digital cameras. The book progresses through a series of projects that progress from basic to advanced photo retouching. Many of the techniques are touched on in other books, but Restoration and Retouching has the best organization and practical details to guide you through the process. The 3rd edition is a near-complete rewrite of the previous text. Organization and clarity are even better than before, and many of the sample images were updated to better illustrate the topic at hand.
Photoshop Color Correction, Kieran, 2003. This book is a visual reference on using Photoshop to get the most out of your digital images. The material is somewhat dated; the coverage is of pre-CS versions of Photoshop. Nonetheless, the techniques remain effective. The book is loaded with detailed examples, instructions, and screen shots to illustrate the theory discussed. This is not a general purpose Photoshop book, but for those trying to get the color right, it is an excellent resource. Several sample chapters are available through the above link.

General Photography: Even if you are a hard core digital nut, these will improve your work.

Basic Photographic Materials and Processes, 2nd Ed., Stroebel, et. al., 2000. The guts of this book come from RIT course notes. This book tears you through a very good year long course in less than 400 pages. If you desire to learn the most about photography in the least amount of time, I know of no better book. This book is on the technical side, however, but gets my highest recommendation. The only failing is that the coverage of digital photography was out of date when the book was released in 2000. Excerpts are available online through the above link.
Kodak Professional Photoguide, 6th Ed., 199. Contains all the information in most first year photography courses, but is not as technical or in-depth as Basic Photographic Materials. It is small enough to tuck into your bag and is filled with handy nomograms and calculators for everything from filters to lenses to flashes. Haul it with you; it is a great field reference. Older editions had the advantage of coming with a 4x5 Kodak gray card.

Color management and color theory:

Real World Color Management 2nd Ed., Fraser, Murphy, and Bunting, 2004. The late Mr. Fraser and his colleagues take on Color Management. All aspects of color management are covered here, from basic theory to how the elements of your digital work flow use and interpret color. The explanations are clear, the advice practical. The new edition covers updated products, as well as adding a chapter summarizing the path your pixels take from capture to output. If capturing and reproducing accurate color is necessary to you, this book should be on your shelf.
Billmeyer and Saltzman's Principles of Color Technology, 3rd Ed., Berns, 2000. This book is not for the faint of heart. Most of the material is taken from notes for RPI graduate color technology courses in the 70's and early 80's. It also contains a wealth of new material relating to digital capture, color management, and measurement technology. If you want a thorough understanding of color theory, this book has what you need.
Digital Color Management Encoding Solutions, Giorgianni and Madden, 1997. These two guys invented PhotoCD, and certainly know their stuff. The book is strong on theory, but is less strong on current practical details. If you want to tackle editing the raw format of images, however, this book is the best there is.
A pair of books, one on reproducing color, the other on measuring it by Robert Hunt condense much of the available research into two volumes. The Reproduction of Colour: 6th Edition, June 2003 goes into great technical detail on color reproduction technology. This is not a simplified overview text; rather it is a comprehensive review of color reproduction. Nonetheless, the information is presented in a readable style, not requiring vast technical background to understand. The companion volume, Measuring Colour: 3rd Edition, January, 2001 thoroughly covers how to measure the colors you produce. This book also contains all the standard color equations and how to use them.
Color Science: Concepts and Methods, Quantitative Data and Formulae: 2nd Edition, by Wyszecki and Stiles, July, 2000 is the classic text on color science. The book focuses on practical implementations of color theory. If you are out to build your own profiling application, this book will rapidly become your friend.

Printing:

Mastering Digital Printing, 2nd edition, Johnson, 2004. This book is a gold mine of information on how to get what you see on screen into print. It concentrates on inkjet printing, and explains the techniques necessary to produce fine art prints.

Hardware:

GretagMacbeth/Munsell ColorChecker targets:

These are carefully calibrated reference standards. The colors include a gray scale, primary colors, and representative natural colors such as skin tones, foliage, and blue sky. The color patches also reflect light similarly across a wide array of illumination sources. This allows the targets to be used to match the colors of natural objects under all standard light sources and color reproduction processes.
The ColorChecker charts come in full size 8x11 and portable 2.5x3.5 inch sizes.

Software:

Photoshop CS4 (upgrade version also available): The standard for all image editing. If you are using an older version of Photoshop, the many new features and far better color management are more than worth the upgrade cost.
Mac OS/X: Having all windows color managed is a tremendous benefit. This operating system is great for digital photography.
Windows XP Pro or Home: With either one, Microsoft has an operating system that supports color management, and works very well for image editing.
Windows Vista Ultimate, Home Premium, or Business: Vista gets a qualified recommendation. Some applications, such as Adobe's CS suites from version CS3 onwards, are at their best under Vista. Built-in operating support for useful file formats, integrated content creation tools, and support for scads of system memory (64-bit editions) are all pluses. A fundamental flaw, however, is in how monitor profiles are handled. Vista's UAC prompts (security warning dialogs that pop up all too frequently) wipe out any monitor calibration. After each UAC prompt, the calibration loader must be run manually.

Online:

This is not intended to be a typical all-inclusive list of links. Instead, the sites below have concise, articulate information with a minimum of extraneous blather.

Bruce Fraser's articles on Creativepro.com are a gold mine of information on Photoshop, color management, and photo editing. This site also has extracts from Real World Photoshop, with the added benefit that the pictures are reproduced at a legible size.
Andrew Rodney's digitaldog.net site also has good information and tips about Photoshop and color management.
For advanced Photoshop tutorials and tips, there is nobody better than Adobe's own Russell Brown. He dreams up methods that are amazingly creative and powerful. His site includes both text descriptions and QuickTime movies showing the application of his tips.
Charles Poynton has perhaps the best color theory information on the web. His site is a bit scattered, but his Gamma and Color FAQs are worth printing out and reading.
No discussion of color management is complete without mention of the International Color Consortium, the industry group responsible for defining the color management standards.

Books

Hardware

Software

Online links