I’d bet that the engineers at Canon and Nikon would be shaking their heads in wonder if they read this book. Even though thru-the-lens (TTL) flash has been around longer than digital cameras, Bryan Peterson is still advocating the exclusive use of manual flash.
Peterson’s advice is to set the flash to manual, determine the distance from the flash to the subject, set that distance in the flash readout and then set the aperture to that indicated in the flash readout. The settings that he recommends for other conditions are permutations of this formula. For example, if you have ambient light that you wish to preserve, Peterson recommends setting the aperture for that purpose, checking the readout for the recommended distance from flash to the subject and setting up your flash at that distance. Peterson’s recommendations are sound, but he essentially changes the electronics in the flash to an automated version of the chart that electronic-flash photographers used to carry around forty years ago. He recommends against using TTL flash.
Yet TTL flash does the same thing automatically. For TTL, in a period of time measured in ten thousandths of a second, before firing the main flash a small burst of light is fired at the subject, from which the flash calculates the proper settings and flash power for an image. This is the same process that Peterson recommends, except that it’s fully automated. That’s why today’s TTL flashes are expensive and internally sophisticated and yet so easy to use. In some cases TTL is far more accurate then flash used as Peterson recommends. For example in using bounce flash, a process wherein the flash in an interior setting is aimed at the ceiling to bounce the light back at the subject, defuse the light beam and provide softer lighting, Peterson recommends increasing the aperture by two stops to make up for the longer distance the light has to travel and then, if that’s not satisfactory adjusting the aperture up or down. I have taken thousands of pictures using bounce flash and TTL, and estimate 95% of the time the exposure was spot on, and in the remaining cases was so close to perfect that a small adjustment of levels in Photoshop was all that was necessary for correction. At a hectic event, like a kid’s birthday party, one doesn’t want to bother with the calculations required by the Peterson method. (Peterson apparently objects to the small preflash.)
There are other problems with Peterson’s book. Besides positioning a flash in the Peterson method to a fixed distance to the subject that may be away from the camera, one may also want to move a flash off-camera for more attractive lighting. This can be done in a number of ways, including a cord from the camera to the flash, built-in infra-red or other non-wired communications between the camera and the flash, and separate radio-control devices. None of these is discussed in any great detail. Similarly, mention is made of diffusing the flash for a more attractive light, but there is no organized discussion of diffusers.
There is nothing wrong with using manual flash, and in a few special situations it may be the only way to get the illumination one wants. But to suggest that TTL flash should never be used is highly misleading. Most books teaching the use of flash will show all the methods. Peterson is the first modern photographer to recommend a return to the old methods. If you want to explore manual flash this book will prove helpful, but please don’t abandon all the more modern techniques that the engineers have created to make life easier for the flash photographer.