In Card Tricks, click CHDK-]Card, and select your .zip file. After the status messages disappear, eject the card, and slide the card's physical lock switch to its locked position. Insert the card back into the camera, and power it up. You should see a brief splash screen signifying that CHDK has launched. Now you're ready to activate your Canon's newfound superpowers.

Shoot RAW to Save the Complete Picture

Your camera processes images a few times in order to spit out JPEGs, compressing and converting the native data that it captures. Even if you set it to record a JPEG at the highest size and in the highest quality, you'll still lose details compared to the camera hardware's inherent ability. RAW pictures--most common on DSLRs--save files in the native format of each specific camera's image sensor. This means that the photos are less compatible with software in general, since the RAW format varies. But the trade-off is that you can process popular camera file formats on a PC, instead of relying on the camera to set white balance and other variables permanently when saving to a JPEG.

On your camera, enter Alt mode by pushing Direct Print or Shortcut. Push the Menu button. Navigate to 'RAW Parameters', activate Save RAW, and you'll see a dot confirming the choice. Push the Menu button again, and exit Alt mode using the same button that you used to enter it. Now a RAW counter should float over your camera's regular remaining-photos countdown, helping you keep track of space for these bigger files. On most cameras, you can toggle RAW mode by holding the shutter halfway, and pressing the joystick to the right.

Apple's Aperture, Adobe's Lightroom, and other photo software can natively read the files from most cameras that have RAW saving built-in. At press time, however, these wouldn't read the unconventional RAW images that we shot using CHDK; you'll need to use a different tool.

I like making simple edits on a PC or Mac with PhotoLine, which natively recognized the files in my tests. Alternatively, you can use other software to alter these true RAW files minimally into DNG images that retain RAW data while becoming compatible with standard image editors. DNG4PS-2, RawTherepee, and UFRaw are good options.

Add a Live Histogram

Your camera likely lets you review a histogram after you take photos, showing the graphed curves that represent color and exposure. If the curve is squished to the left and leaves empty space on the right, for example, your photo is probably too dark and underexposed. If the curve shows values across the entire graph, your image has captured a dynamic range, maximizing the possible highs and lows.

Those details are great for reviewing shots or editing in Photoshop, but they can be even more helpful as live feedback when you are composing photos. Many high-end cameras show live histogram details, but your point-and-shoot probably doesn't. The CHDK software can add that feature.