Digital Focus: Resize Photos; All About Zoom

Feature: Resizing Your Photos

There you were, photographing your kid's first piano recital. And although you might not want to recall your little one's particular rendition of "Fur Elise" in detail, you did capture some heartwarming visuals of the performance with your new 3.3-megapixel digital camera. So the next day you e-mail a few of the best shots to your friends, and you get nothing but complaints:

"The pictures are too big to fit on my screen!"

"You overloaded my e-mail account with huge files!"

"Why didn't you invite me? I love recitals!"

I can't help you with the last one (though, admittedly, I am good at making up excuses--try, "they only gave each family two tickets"), but I can certainly help you change the size of your images. It's easy to do, and it's probably the single most common edit you'll ever make to your pictures.

Why We Resize

Your digital camera can take pictures in a variety of resolutions, though most people stick with the biggest format most of the time. That way if you happen to capture Bigfoot on film, you'll have more pixels with which to make an enlargement.

But having more pixels isn't always a good thing. When you send an image through e-mail, big images equal big files that can clog e-mail accounts and take a long time to download. Right here in this newsletter, for instance, we invite you to enter a weekly digital photo contest--but entries need to be no larger than 640 by 480 pixels. Why? Good question! I receive about three dozen entries each week, and that many 3.3-megapixel images would quickly overload my e-mail storage.

And when you display a digital image on the computer screen, the picture should actually fit. Too many pixels might make the picture appear to be much larger than the monitor, and you'd need to scroll around to see different parts of it--like looking at an elephant through a microscope.

Shrinking Pictures

Luckily, the solution is simple. Virtually all image editors allow you to resize pictures. Open a file in Paint Shop Pro, for instance, and select Image, Resize to open the Resize dialog box.

There are several ways to resize. The Resize dialog box lets you change the image by pixel size, percentage of the original, or based on print size.

Before you go any further, make sure the "Maintain aspect ratio" option at the bottom of the dialog box is checked. That'll keep the image's proportions correct as you resize it. I typically find that the first option--pixel size--is the most useful. If you want to send a picture through e-mail, for instance, just change the width to 600 or 700 pixels; the pixel adjustment for the height will change accordingly, based on the image's aspect ratio. Click OK, and the image shrinks to a fraction of its original size. Save the new image with a different file name--that way you've got the original, high-res version of the picture in case you want to do more editing or print it later.

What size you choose depends upon where the image is headed. If you're posting images on EBay, for instance, you can probably shrink them down to 400 or 500 pixels. If you are making a portfolio of images for your Web site, you might make them a bit bigger so visitors can see more detail in each photo.

I rarely use the option marked "Percentage of original," so I won't discuss that here.

You might occasionally want to use the third option, "Actual/print size." Consider this: Suppose a friend wants to print a 5-by-7-inch version of your piano recital photo, and she asks you to e-mail a picture that's just big enough for the job. Open the Resize dialog box and click on "Actual/print size." Set the resolution to 200 pixels/inch--that's what most ink-jet printers are optimized for. Now enter a width of 5 inches and make sure the height is about 7. If the height comes up a little short, like 6.5 inches, you might want to enter a 7 in the height box and let the image editor generate the width. Click OK and save the file.

Enlarging Pictures

Most of the time, you'll shrink your pictures--enlarging them just doesn't work that well. Suppose you want to print a 1-megapixel image in an 8-by-10-inch format. Don't bother; there aren't enough pixels, and the result will be blurry and jagged. In essence, you'll be able to see individual pixels in the picture. Using the resize tool won't help, because the program simply can't smoothly add new information to the picture.

That said, there is a workaround. (In other words, I just lied to you.) Check out "Dave's Favorites" for a program that does indeed let you enlarge digital images and still wind up with acceptable quality.