Maybe you've heard about slit-scan photography, a process in which an image is developed one thin 'slit' at a time. Probably you haven't! But if Photo Booth has taught us anything, it's that the joy of taking wacky warped pictures is universal. And the Slit-Scan Camera iPhone app is like Photo Booth on acid.

What is it?

Slit-Scan Camera, Free, iPhone. Slit-Scan Camera replicates, ya know, slit-scan photography, giving you some seriously strange glimpses of the world around you. You can set the direction the size of the slit, which also determines how quickly it moves down your display. You can use your front of back camera. But where any one of Photo Booth's effects is pretty straightforward and singular, Slit-Scan Camera can produce a variety of bewildering images, depending on how big you set the slit, how much you move your phone while it's developing, and, most of all, what you're pointing it at. Once you get a sense of exactly what's going on, the fun comes from trying to see where the technique can take you. It's not immediately obvious.

The app's free to try out, though a $2 in app purchase lets you shoot long, panoramic shots, gives you the option to turn on continuous autofocus, white balance or exposure, and makes the annoying iAd disappear.

Who's it good for?

People who like the wackier side of iPhone photography (if you're into any side of any cellphone photography, you should be submitting to this weeks shooting challenge!) ; people who are celebrating today's unofficial holiday.

Why's it better than alternatives?

For a feeble mind like mine, the potential for what you can make with the slit-scan process is not immediately apparent. It takes some experimenting, which is fun. A lot of experimenting, actually. And while photo effects are cool, it's not hard to predict what they're gonna do to your shot. Since slit-scan is developing the photo in a fundamentally different way, the results vary wildly depending on what you're shooting and how it's moving. What I'm saying is that for the photographically curious, there's a lot you can do with it.

Slit-Scan Camera for iPhone

How could it be even better?

Even with the helpful "info" overlay, both the UI and the slit-scan process itself are kinda confusing and could stand to be explained briefly at the outset. Also, the "pinch" gesture for resizing the slit was kind of awkward for me.

Slit-Scan Camera for iPhoneSlit-Scan Camera for iPhone | iTunes

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Video music: Kevin MacLeod