Digital Focus: Resize Photos, All About Zoom

Tools and tips that help you shrink and enlarge your pictures.

Dave Johnson

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.

Dave's Favorites: Enlarging Pictures With Genuine Fractals

So, you've got a great picture that you want to use for 8-by-10s. The only problem? The resolution is too low, and your attempts to print it have not met with success. What to do?

Try Altamira Group's Genuine Fractals. It's a plug-in filter for Adobe PhotoShop that works in any image editor that uses PhotoShop plug-ins. Genuine Fractals delivers "resolution on demand." Essentially, it allows you to enlarge digital images to several times their original size. The program uses some fiendishly complex fractal mathematics--which may as well be magic as far as I'm concerned--to scale the picture up without the tell-tale pixilation you'd usually get from enlarging a digital image.

Genuine Fractals has its limits, of course. You can't make a billboard-size image from a 1-megapixel photo and expect it to look good. On the other hand, I've used the program to make posters from 3.3-megapixel images, and the results are nothing short of astonishing.

Genuine Fractals comes with some digital cameras, or you can buy it for $159 at the Adobe Web site.

Q&A: Getting to the Bottom of Zoom

I have the Epson 3000Z Photo PC camera. The camera has a 3X optical zoom. I purchased a 2X telephoto lens. Does that give me a true 6x zoom? Will I ever be able to buy a bigger telephoto lens for this camera?

--Larry E. Jacobson, Eau Claire, Wisconsin

Yes, Larry, you can combine zooms in this way and the effective magnification is just what the math would suggest. If you zoom all the way out to 3X, you'll have a true 6X zoom. Of course, you can throttle back on the camera's built-in zoom to reduce the overall magnification as well.

If you're looking for add-on telephoto or wide-angle lenses for your camera, your first stop should generally be the camera maker's Web site. Often, you can find lenses and filters that are custom-made for your camera. After that, though, be sure to check out my favorite digital camera accessory company, Tiffen. The folks at Tiffen make a wide variety of add-ons for digital cameras. To use them, all you need is a standard adapter that acts as a bridge between your camera's built-in lens and the accessory lens. Indeed, Tiffen sells adapters that let dozens of digital cameras use the company's add-on zooms.

Hot Pic of the Week

Get published, get famous! Each week, we select our favorite reader-submitted photo based on creativity, originality, and technique. Every month, the best of the weekly winners gets a prize valued at between $10 and $100.

A gentle reminder, folks: We disqualify some really wonderful pictures every week because the submissions don't follow the rules. Be sure to include everything we ask for in your e-mail message, including a description of your picture and your complete contact information, or your entry is wasted!

Here's how to enter: Send us your photograph in JPEG format at a resolution no higher than 640 by 480 pixels. Entries at higher resolutions will be immediately disqualified. If necessary, use an image editing program to reduce the file size of your image before e-mailing it to us. Include the title of your photo along with a short description and how you photographed it. Don't forget to send your name, e-mail address, and postal address. Before entering please read the full description of the contest rules and regs.

This week's Hot Pic: "Pensive in Pink," by John Smick, Iowa City, Iowa

John writes: "We took the digital camera to brunch one morning and snapped this picture of my daughter Maeve sitting in a window. I used the camera's spot metering function so she was nicely exposed relative to the much brighter background. I really like the partial profile angle. Although the picture isn't framed as nicely as I'd like, it was one of those quick snaps that turned out to really surprise us."

Hot Pic of the Month: Each month we choose one of our weekly winners to be the Hot Pic of the Month. For March, we chose "Spanish Cross," by Susan Trudeau, taken in the Spanish town of Ronda. The picture makes good use of depth of field and PhotoShop's softening filters. Congratulations to all the other weekly winners, as well. Keep entering, and your photo might be featured here soon!

We want your feedback! Send your comments, questions, and suggestions about the newsletter itself to comments@bydavejohnson.com. If you have a question that you'd like to see answered in the weekly Q&A, send it to question@bydavejohnson.com.

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