Have a question about digital cameras, photo editing, or digital photography in general? That's why I'm here. (Of course, my cat would tell you I'm here to provide a comfy lap for afternoon naps.) Once a month or so, I dig into the mailbag and answer reader questions. Have one of your own? Send it to me and I'll do my best to answer.

Better Indoor Action Photos

Recently, I was taking pictures at an indoor martial arts tournament in a gymnasium, and everything turned out blurry--even photos of people standing still. The photos of moving people were a blurry mess. I set the camera on Sports mode. What did I do wrong?
--John Borys, Seattle

You had the right idea, John. Sports mode uses a faster shutter speed, which is what you need. But indoors, that's not enough: The camera needs help to get the shutter speed fast enough to take sharp pictures. You'll also need to increase the camera's ISO, which controls its sensitivity to light. A higher ISO also means more digital noise in the photo, but that's the tradeoff you have to make when shooting high-speed action photos indoors.

A faster lens would also help. Lenses are rated by their maximum aperture. An f/5.6 lens, for example, is less expensive than an f/2 lens, but the f/2 lens admits quite a bit more light, allowing you to shoot it with a faster shutter speed. The next time you shoot indoors and try to capture the action, John, pay attention to the shutter speed your camera is using. Unless your shutter speed is about 1/500 second or faster, you'll probably end up with blurry photos.

Read "Take Sharper Pictures" for details on shutter speed and ISO settings.

Claymation Success

Your columns a few weeks ago on creating a stop-motion animation really got me going. I always wanted to try my hand at "claymation," so my 10-year-old daughter Catherine and I rolled up our sleeves. She made the figures and moved them. I pressed the shutter and stitched the frames together with Premiere Elements. You can see all 18 seconds online at YouTube
--Dan Hutt, Dartmouth, Nova Scotia

That's awesome, Dan, thanks for sharing. For anyone who missed my recent newsletters on creating a simple stop-motion animation, they're online, too:

1. Make a Stop-Motion Movie, Part 1
2. Make a Stop-Motion Movie, Part 2

Don't Worry About Dots per Inch

The pictures from my camera are always 72 dpi when I download them to my computer. I had always thought that was the default. I friend of mine, who has a different camera, downloaded some of his pictures to my PC and they were 300 dpi. My camera is set for SHQ (Super High Quality) and I don't think there is any other place to change the resolution setting. What's wrong and how do I fix it?
--Dolores Mayer, Boston

The good news, Dolores, is that this is not a problem at all and you can completely ignore it.

The dpi setting that your camera embeds in your digital image files has no real significance. The resolution of a digital photo is measured in just one way: how many pixels it has. If you take two photos--from two different cameras--and both are 2000 by 3000 pixels (6 megapixels), they will be identical in every meaningful way. That's even if one camera marks its photos as 72 dpi and the other camera marks its photos 300 dpi.

Dpi, or dots per inch, is useful when figuring out what size a picture will appear when displayed on a computer screen or when printed on paper. You can take the resolution and divide it by the dpi, and that tells you the physical display size. Since most monitors display at 72 dpi, many cameras embed the 72 dpi value in the picture. Other cameras use 300 dpi, since that's a common print resolution. Either way, it does not affect the photo, nor does it affect the display or print quality. It merely serves to confuse people, and is safely ignored.

Printing From Digital Zoom

My digital camera has a 5X digital zoom. As a novice to the digital camera world, I discovered that this feature offers a wonderful opportunity to do selective enlargement/cropping of the various parts of a given photograph. My question: Can I print any of these camera-induced cropping images directly from the digital camera? Or do I need to use some sort of software to accomplish the same thing, which leads to some degradation of the image?
--Al Stohl, Madison, Wisconsin

That's a good question, Al. I haven't written about digital zoom in a while, so this is a good time to revisit the subject.

In general, I recommend that folks avoid digital zoom--simply turn it off completely, if your camera lets you. While optical zoom magnifies the image using the camera lens, digital zoom simply magnifies the pixels, and that's a pretty low-quality way to zoom in on a scene. If you want to zoom in and crop a photo, it's better to use image editing software on your PC (programs like Adobe Photoshop Elements, Microsoft Digital Image Suite, or Corel Paint Shop Pro, for example). You'll have significantly more control over your final composition and get better results. I really recommend doing your cropping on the PC, not in the camera with digital zoom.

That said, if you do want to use digital zoom and print your photos directly from the camera, you certainly can: Most inkjet photo printers can connect directly to your camera without involving a PC at all.

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 $15 and $50.

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 regulations.

This Week's Hot Pic: "An Apple a Day," by Matt Hopkins, Exton, Pennsylvania

Matt writes: "I took this picture when my wife and I went to a local orchard here in Pennsylvania. We were eating some apples when I began to throw them up in the air and take pictures of them. After taking about 20 or so photos, I finally got one that came out sharp and in focus!"

See all the Hot Pic of the Week photos online.

Have a digital photo question? Send me your comments, questions, and suggestions about the newsletter itself. And be sure to sign up to have the Digital Focus Newsletter e-mailed to you each week.