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Picture-Perfect Pictures

A digital photography veteran offers the best tips and tools.

I’ve been a professional photographer for nearly 20 years, and in the process I’ve shot thousands of rolls of 35mm negative film. As you might imagine, my recent transition from film to digital was not without pain. What follows is a brief compendium of some of the things I’ve learned (mostly the hard way), and some tools I find useful.

Pick a flexible camera. Digital camera choices have never been greater, more affordable or more confusing. Virtually all offer complete automation of focus, exposure, and color balance, but there are many situations where this will yield poor results.

Look for a camera that also allows manual settings–and provides an exposure histogram. Also look for one that offers the lossless RAW image compression format as well as the universal (and lossy) JPEG format.

Consider a DSLR; models such as the Nikon D-70 and Canon Rebel XT are now less than a grand with a decent lens, and of course an SLR lets you pick from a large selection of lenses and other accessories (and perhaps use some of your 35mm gear) as your needs change.

Research and try before you buy; take along your own digital film and put your candidate cameras through their paces (preferably with the same range of subjects and lighting conditions). View and/or print the results to evaluate each.

Choose your digital “film.” Like its celluloid ancestors, the digital equivalent comes in a wide variety of flavors. These fall into three main categories: type, size, and speed.

Two memory card types currently lead the pack: compact flash (CF) and secure digital (SD); I’d stick with one of those. CF has the largest installed base, but SD is coming on strong–particularly in smaller gear because of its postage-stamp size (too small for my taste; I prefer some heft in such expensive little chips).

Within types, capacities range widely, currently from 16MB to 8GB (in CF–SD tops out at 2GB). Speed refers to how fast a card can read and write; many cameras can’t take full advantage of the fastest cards (yet), but you’ll notice the difference when downloading to a PC/Mac via a FireWire or USB-2 card reader.

I’ve more or less settled on SanDisk cards ($17-$725), which come in regular, Ultra, and Extreme versions, differing mainly in speed, ruggedness, and testing. These consistently rate at or near the top in bang for the buck, and I’ve never had one fail me in tens of thousands of shots.

Use the right color space. Every digital sensor has a range (or gamut) of colors it can capture. In addition to the nearly universal sRGB, many higher-end cameras offer a larger gamut called Adobe RGB (introduced in 1998).

In this case, bigger ain’t necessarily better; most printing processes–including virtually all one-hour labs–can only reproduce approximately the sRGB range. Shooting in Adobe RGB forces these printers to compress out-of-range colors into their smaller space, often yielding flat, ugly results.

Use Adobe RGB only if you know your printer or other output device will support it.

Nail exposure with the histogram. Current digital sensors are more similar to slide film than negative film, and are similarly less forgiving of exposure errors. For good results, experts say your subject should be no more than .3 stops over and .5 stops under ideal exposure (versus negative film’s typical 3-stop latitude).

If in doubt, err toward underexposure (the opposite of film); details often can be pulled out of shadows, but blown highlights are gone forever.

The histogram (standard on better digital cameras) is a bar graph of the distribution of pixels from black to white, and is your best guide to getting a good exposure. If it’s skewed too much to the left or right, the image is underexposed or overexposed, respectively. Every histogram will be different, but by examining them regularly and comparing them to your printed results you’ll become adept at reading your histograms.

Trust the histogram more than the LCD image display; even on pro cameras the latter often looks overexposed. You can learn to compensate for this, but the histogram provides a truer picture.

Do some target practice. Simply putting a white sheet of paper in the scene with your subject for a test shot will yield a spike in the histogram to help judge your highlight exposure; it should be close to but not at the right edge.

A more sophisticated approach involves a target that has black, 18-percent gray, and white patches, resulting in three distinct spikes. You can use the same target–white, gray, or all three–to set a custom white balance.

White balance compensates for the varying color temperatures of different light sources, much as one uses filters or different film types with film. Custom white balance is often more accurate than auto or one of the usual presets, especially in mixed lighting.

A line of high-quality digital targets is available from companies such as PhotoVision > < ($59-$291).

Take advantage of ISO. Most digicams offer “film speeds” up to at least ISO 400, and some DSLRs go as high as 6400. Higher speeds mean more “noise” (the digital equivalent of film grain, most noticeable in blacks), but sensors are getting better all the time.

Try cranking up the ISO to take advantage of available light and make less use of flash for better-looking shots.

Consider RAW for important or tough shots. The RAW format (an alternative to JPEG on many cameras) is the “digital negative.” A RAW file is saved without any of the processing (or lossy) compression applied to JPEGs, producing the highest-quality image the camera is capable of capturing. RAW also provides much greater ability to manipulate the image than does JPEG, allowing one to better compensate for incorrect exposure, white balance and other problems.

A big downside is that RAW files are much larger than JPEGs, and they must be processed and saved under a different file format (such as a TIFF or JPEG) before you can do anything with them, significantly slowing down your workflow.

Every camera offering RAW provides software for working with RAW files, and Photoshop directly supports most RAW formats. If you get seriously into RAW work, look into CaptureOne ($99-$499), whose forte is automation and batch processing of RAW files.

Enhance your images. One word: Photoshop. Photoshop CS2 ($599) is the standard of the industry, and Photoshop Elements 3 provides all the tools many photographers will ever need for $99.

I can’t begin to describe Photoshop here, but literally thousands of Photoshop books and courses are available everywhere. One I can recommend is Deke McClelland’s book/CD course, “Adobe Photoshop CS One-On-One” (O’Reilly, $39.95). He has a similar course for Elements 3, and also authors the popular “Photoshop CS Bible” (Wiley, $39.95), as well as “Dummies” books for both Photoshop and Elements.

For a digital photography emphasis (and lots of useful digital photography information), check out Martin Evening’s “Adobe Photoshop CS2 for Photographers” (Focal Press, $45). All of these books are in a continuous state of revision as Photoshop versions change; look for the edition that matches your version.

Manage your collection. Recent versions of Photoshop and Elements provide all the photo cataloging and management tools many photographers will need, and iPhoto is a very nice free program for Mac users.

However, there are also several programs that specialize in this task, with the usual benefits of such specialization. My choice is iView MediaPro , $199), available for both Mac and Windows. (A less expensive version, iView Media, has the most important features for $50.) I use iView for most of my photo viewing and cataloging tasks, including batch rotating and renaming, shot selection, minor editing and cropping, proof printing, down-resolution (which is handy for e-mailing) and quick slide shows and Web pages.

Calibrate your monitor. Particularly if you do your own photo printing, a major source of frustration and waste is printed output that doesn’t match what you see onscreen. While the profiles provided with your PC/Mac, monitor, scanner and printer will get you in the ballpark, they’re often only approximate, and monitors (particularly CRT models) drift over time.

If you’re into color editing and printing, get a monitor calibrator–it’ll save you money in the long run. This is a colorimeter you stick to your CRT or hang over your LCD, along with software that runs through a calibration routine. After calibration, you print a color chart and scan the results back into the system (either with your scanner or a spectrophotometer included with the fancier systems).

By characterizing each printer/ink/paper combination you use, you’ll achieve WYSIWYG output without trial-and-error. One well-regarded system is the Monaco EZcolor/Optix-XR software/hardware bundle ($348).

Pick a photo printer. These days, many inkjet printers do a credible job of printing photos as well as text, but most tend to excel at one or the other, not both. Choosing a printer can be just as complex and confusing as choosing a camera, but there’s a wealth of information on the Web, free for the searching.

While HP and Canon make some excellent printers, for my money Epson >www.epson.com

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