Book Review: Digital SLR Astrophotography

Book review: Digital SLR Astrophotography
ISBN number: 9780521700818
Price: $45 US
Author: Michael A. Covington
Publisher: Cambridge University Press

Astrophotography has always involved a skill set requiring precision, patience, and a lot of trial and error. The learning curve has been steep, to say the least, but with the advent of Digital photography a larger and larger number of amateurs face this learning curve. Unfortunately, Digital photography also demands a different set of skills not documented before. With the exception of the few books that have tackled the subject in one way or another, amateur astronomy using DSLRs still lacks one good all-around, comprehensive introductory text for beginners. A few books have concentrated on the processing aspects of Digital imaging, and a few older books have updated sections on film photography with mention of Digital cameras, but Covington's work here is one of the first to approach DSLR astrophotography as its primary focus. Digital SLR Astrophotography does a good job of introducing the interested amateur to the subject while providing enough information to allow a beginner to advance in the hobby.

Astrophotography's 217 pages are divided into 14 chapters. In the first part of the book, Basics, Covington spends four chapters discussing DSLR options, technical issues unique to this format, problems associated with using electronic sensors in the cameras, and a few simple projects to introduce the reader to some immediate success using the camera. Throughout this section Covington mostly refers to Canon or Nikon cameras, which are the two main brands currently on the market, but he pays little attention to other options aside from a brief mention. His treatment of software is similar, however, he does mention freeware options which any beginner is well advised to try before investing in an expensive processing package. Most examples used in the book refer to Adobe Photoshop or MaxDSLR.

In part two, Cameras, lenses, and telescopes, Covington uses a chapters to explain how to couple the camera to the telescope and how different configurations how different effects on the final image, modifying the light path with focal reducers (Meade or Celestron), the pros and cons of using camera lenses piggybacking to a telescope, issues and solutions to focusing Digital cameras, the necessity of tracking the sky and how to go about it, keeping power to the camera and finally, different types of Digital sensors in the cameras and their response to various wavelengths with and without filters. Throughout this part of the book Covington references Meade and Celestron products but with one or two exceptions, ignores what has come to be the third major supplier of telescope products, Orion Telescopes. Covington does a good job of providing illustrations that clarify some of the technical issues he discusses in the text. These are generally excellent, and go a long way towards clarifying the various lenses and focusing options. Covington also does a good job for presenting the reader with the various choices and amateur astronomer has to make, including guiding options and focusing aides. Unfortunately, in the case of the latter, Covington mentions that it is easy to create a Hartmann mask but fails to deal instructions, instead referring the reader to his earlier book Astrophotography for the Amateur.

Part three, Digital image processing, covers a topic that can be most confusing to new astrophotographers. Covington explains the difference between dark, bias, and flat frames well but consistently uses MaxDSLR for his examples. This obviously works well for readers already using that particular software package, but may not be as clear for beginners using some of the free software packages. Nevertheless, this section is a real strength of the book, and will definitely aid the beginner in understanding some of the complexity involved in serious DSLR astrophotography.

An appendix of about 10 pages briefly mentions WebCams and their use for planetary photography. The inclusion of this seems odd, and out of place, as if, after having read the entire book, a beginner decides DSLR photography is not for them and perhaps they would be interested in WebCams instead.

Overall, Covington has done a good job of providing an introduction to the topic that also presents the reader with some of the options they can face in the hobby as well as potential solutions to problems that will inevitably occur. As a primer the book is first rate. Covington's strengths are evident in his handling of some of the more confusing topics; he explains them well. The diagrams provided are clear and informative. However, a serious drawback of the book is that photographs (all black-and-white} are often unhelpful and in some cases confusing. Perhaps due to the black-and-white nature, this can be annoying and for a book that cost $45 may leave the reader feeling less than inspired. For example, when discussing the pros and cons of modifying an DSLR to be more sensitive to hydrogen alpha emissions, side-by-side photos are given to display the difference. Now, Covington's point is to show how well an unmodified camera can do, so some similarity is expected, but I have yet to detect any difference between the two photos. Secondly, for a book whose purpose is astrophotography, it is criminally bereft of any striking photos that typically inspire beginners into the hobby in the first place. Covington would have been well served by including even a small section of color plates illustrating some of the superior photos being taken with relatively inexpensive equipment by amateurs using DSLRs. Still, Digital SLR Astrophotography fills a much needed role as an introductory text on the subject.