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I'm convinced that most digital photographers aren't aware of the need for the highest possible resolution when they take photos intended for publication
   technofile
Al Fasoldt's reviews and commentaries, continuously available online since 1983

T e c h n o f i l e
Why some publications might not want to get your digital images


Oct. 19, 2003


By Al Fasoldt
Copyright © 2003, Al Fasoldt
Copyright © 2003, The Post-Standard

   Digital images aren't always what they seem. Sometimes they are less than meets the eye.
   The problem is simple to explain but hard to deal with. Some digital pictures don't have much resolution. In other words, they don't have much detail.
   Looking at low-resolution pictures on a computer screen isn't a problem. They look OK most of the time. But they'll look dreadful when you print them on your fancy new ink jet. The printer needs a lot of detail to make a photo look good. Without the detail -- without the proper amount of resolution -- your pictures will be OK on the screen and passable as wallet-size prints. But they won't look good at 5X7- inch or 8X10-inch sizes on your wall.
   Resolution is a proud old term that predates photography by hundreds of years. It was a gauge of the "resolving power" of the earliest microscopes and telescopes. Isaac Newton, one of the great masters of early telescope design, was able to "resolve" -- identify, in other words -- more detail in the night sky each time he improved his telescopes.
   Think of "resolving power" the same way you think of a cell phone conversation that's riddled with static. The guy on the other end of the line can barely be heard, much less understood. When he tells you to call him back at another number, you can't make out half of what he says.
   The medium -- the cell phone connection -- didn't have enough resolving power. You thought you heard a "3" and maybe a "6" and a "5," but the rest of the phone number was lost in space.
   There's no way to make up that phone number from the few digits you heard. Likewise, if you buy a new digital camera and set it up the wrong way -- I'll tell you the right way in a moment -- you're likely to fall into the low-resolution trap. Your digital photos will have some of the detail that's in the scene but not enough to produce a good picture.
   And that, in turn, brings us to the question a reader posed last week. Why, asked Manlius artist Sallie Bailey, are some publications afraid of digital photos? They insist on getting traditional photographs instead.
   The answer? It's that word again -- resolution. I'm convinced that most digital photographers aren't aware of the need for the highest possible resolution when they take photos intended for publication, whether in a newspaper, magazine or book. As a result, the pictures they submit sometimes can't be printed large enough on the page.
   Remember: Images need a lot of resolution, a lot of detail, to be printed. This is true no matter what printing method is used. Prints on your Lexmark need a lot of resolution, just as prints published in a magazine do.
   Here's a quick comparison that shows what I mean. Your computer monitor needs only about 100 separate image detail elements in each inch of a photo to show it perfectly. Your printer needs 600 or more. (By the way, "separate image detail elements" is an awkward way to say something this important, so photo experts usually call them "picture elements," or "pixels.")
   Let's translate this into plain English. Your digital camera has a resolving power -- sorry, I mean resolution -- expressed in millions of pixels, usually called "megapixels." Let's say it's rated at 3.2 megapixels. That's a lot. That's more than 3 million separate image detail elements.
   Does that mean all the pictures you take will have 3.2 million separate pixels of good stuff in them?
   Not at all. And that's why setting up a digital camera is so important.
   For reasons that I've never been able to figure out, camera manufacturers go to a lot of trouble and expense designing high- resolution cameras and then sell them with an invitation to turn all that high-quality stuff off.
   You've probably seen that setting in your own camera. It's labeled "Quality" or maybe something else. Maybe it's even called "Resolution." Whatever it's called, the setting gives you a chance to do a dumb thing. It lets you turn down the resolution.
   Never do that. You paid for a camera with good resolution; don't turn it into a cheap camera with bad resolution. Keep that setting all the way up.
   (There's another setting on most cameras that changes image compression. I'm not referring to that setting. But the same principle applies: Keep compression as low as possible. You want all the quality you paid for.)
   Back to last week's question. Editors of newspapers, magazines and books feel frustrated when they receive digital photos that don't have enough resolution to print. No matter how good a picture looks on your screen, it won't look good in print unless it has abundant resolution.
   But how much is enough? Pictures that are sharp, with bright, clear colors, can get away with lower resolution numbers than pictures that are a little fuzzy and dim. But here's a quick guide: If the photo you want to submit has fewer than 1,000 pixels in its longest dimension, it's probably not going to print well. If it has more than 2,000 pixels in the longest dimension -- and if it's sharp, with good contrast and bright colors -- it should make a good print.