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Photographs can really add to a story. A picture is really worth, a few column-inches. Digital cameras and Internet distribution of scanned images make it a lot easier to get pictures and move them around. But digital has introduced some confusion as well. There are various formats to consider, and some details that affect image quality.
It's total dots, not dots-per-inch!
The absolute biggest source of confusion out there is something called "dpi" or dots-per-inch. An often-quoted statistic is that high-quality images begin at about 300 dpi (both QST and CQ give specs that say images submitted should be at least 300 dpi). But if you look at the image created by even the best digital cameras, you'll see they're just 72 dpi. So, can they take magazine quality photos, or not?
Yes, they can. And to figure out how, for a minute we need to forget the inches, and just count the dots.
The entry level of good-enough digital cameras begins with the one-megapixel class. That means there are about a million image-forming dots captured by the camera. Those dots are arranged in rows, and a typical array will have 756 rows, each with 1024 dots lined up side by side, left to right (which doesn't quite add up to a million, but don't sweat it).
OK, let's bring back the inches. The camera is rated at 72 dots per inch, and I'm not going to try to explain why. But do the math, and 1024 dots in one row divided by 72 equals a picture 14 inches wide.
A 14-inch wide picture with 72 dots per inch isn't going to do anyone any good. Fortunately, image-processing software can squeeze the dots closer together. So put the pixels in a vise, crank in a little more simple math, and press 300 of those pixels into each inch. The picture shrinks to about 3½ inches wide (and 2 ½ inches tall)
Now we're talking dimensions real people can use. Take a good picture with your one-megapixel camera, and QST can use it in about a quarter-page. Spend more money on your camera, upping the total to three-megapixels, and the magazine can print a picture about seven inches wide with the same quality. Newspapers can get by with less quality, but for practical purposes you want to stay in the one megapixel class or better.
OK, who should do the squeezing? Probably not you! A pro with the right software can work a fair amount of magic with a digital image. But even a pro will probably want to send the "raw" picture and let the magazine's editor do the manipulation.
The Web, on the other hand, is a different animal. Pictures for web use stay at 72 dpi, and now, we'll start measuring your monitor instead of paper.
If you're using a 15" monitor, odds are you have it set for 800x600 pixels. That means you can fit 800 pixels left-to-right across the monitor. So that picture we took before with 1024 dots in each row would be significantly wider than the monitor. You'd have to scroll left and right to see all of it. If you have a 17" monitor, you probably have it set for 1024x768, and the picture would fill your monitor nicely.
When people design for the web, they have to make some compromises. Much as they'd like everyone to view their creation on a nice, big monitor, the fact is that an awful lot of web users have those 15 inchers, looking at less than 800 pixel-wide viewing areas (once you subtract the space needed for the browser frame and maybe a scroll bar). Most pictures on web sites are less than 400 pixels wide. And we'll say more about that in the next section on compression.
Format and Compression
Most digital cameras save images in the JPEG format, and most allow you to choose between several levels of compression. Many cameras also have an option for taking pictures with a smaller image size than the maximum size. This is popular, because with more compression and a smaller image, you can fit many more pictures on whatever storage medium your camera uses. But the trade-off is image quality.
If you want a publication to use your picture, shoot it with the lowest compression and biggest image size your camera allows. A few cameras even allow you to shoot uncompressed pictures, using the TIFF image format.
JPEG compression is "lossy." The more compressed the picture is, the softer it gets, and you can see some square, blocky "junk" on the edges of what should be sharp objects in the picture. That's why you want to keep compression to a minimum. TIFF allows for some compression, but it's not lossy. A TIFF image doesn't degrade the picture at all. The trade-off with TIFF is that file sizes are bigger. Much bigger.
And big files can be a problem. First, your camera won't hold very many pictures. A really good, three-megapixel camera using JPEG and light compression uses about a megabyte per image. The same picture, stored as TIFF, can be two or three times that size. And here's where a professional photographer's secret comes into play. The pros get those really good pictures you see in the magazines by taking lots and lots of pictures of the same thing, and throwing away all the bad ones. OK, maybe most of their "bad" ones are better than your "good" ones, but the secret is that if you shoot the heck out of a subject, a few select pictures will stand out. But if you can only fit 15 pictures in your camera before you have to run back to the computer and download them, you're limiting the chances for that one really good shot. So you buy the most memory you can afford for your camera, and you compromise (a little) on compression.
Another problem with big image files is how you get them from one place to another. Sending a picture as an e-mail attachment is popular. But if you have a dial-up connection, sending a one-megabyte file takes a very long time. People who swap high quality images regularly need high-speed DSL or cable connections. If you've got a bunch of images to send, you might need to resort to burning a CD and sending it snail-mail!
Once again, the web stands this discussion on its side. You might like to have big, high-quality pictures on your web site, but you won't do it. For those people with dial-up Internet connections, and pictures come in s-l-o-w-l-y. So you keep the pictures small, (usually less than 400 dpi) and compress them a lot. That one megabyte picture that came out of your camera may be only 15 kilobytes by the time it's processed for the web. Your camera can't make these adjustments - that's done in image processing software.
And here's an important point because it's a problem that happens so often: the trip from the camera to the web is a one-way voyage! Once a picture has been shrunk and compressed for the web, you can't blow it up and use it in a magazine. Well, you can do it, but makes a poor picture. But people send these tiny pictures to magazines all the time. It drives the editors crazy.
What about Video?
Just to be complete, let's look at the option of using a frame of video lifted from your camcorder. There are lots of frame-capture devices on the market that let you freeze frame and save it as a digital file.
The specs on that picture are 640x480 at 72 dpi, already pretty low resolution. But for a VHS camcorder, the real quality is lower than that - maybe a usable 300 pixels across the screen. That is WAY below the 1024 pixels of the bottom-end one-megapixel camera. Digital video cameras are a little better, but the fact is that television, invented in the 1930s, is a very low-resolution medium. Newspapers and magazines will use images from television or video only as a last resort, if there is no other, better image available (or to get some wacky style their art director is going for).
High-definition television, when it trickles down to the consumer camera level, is a big improvement -- about as good as today's one-megapixel cameras. But the digital still cameras have already gone way past high definition video in image quality.
Will they use it?
OK, now that we've learned a lot more than we ever wanted to know about digital images, what are the chances of a newspaper, magazine, TV station or web site using it?
The answer is not good, not good, not good, and maybe.
Newspapers and magazines employ professional photographers, and it they're covering your event, they'll send a photog to get the pictures they want. If you tell them about the story after it's already over, and send your own picture, you've really limited your chances of getting it published in all but the smaller newspapers. But then a lot depends on how much they want the story and the picture. You will see "amateur" pictures of dramatic events that were not covered by the pros (the 8mm home movie of President Kennedy's assassination being the most famous). It's become much more common in the last 10 years.
Television is about the same. Funniest home videos notwithstanding, you'll have to have something pretty compelling to get them to put your home video on the news. Invite them to your event, and they'll shoot what they want.
Local web sites are another story. They don't have the staff to go out and get the pictures they want, and yours are probably welcome.
But, at least you're well prepared to send photos to CQ and QST.
