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Digital Photography Hacks
By Derrick Story
May 2004
More Info

HACK
#89
Capture Pictures of Your TV Screen
You can photograph images of your television screen just as easily as any other subject, as long as you know the secret camera settings
[Discuss (0) | Link to this hack]

Your brain might forget that a television picture is really a series of scan lines moving faster than the eye can detect. But the camera isn't fooled so easily, and often, first attempts at capturing TV images result in mysterious black bars spanning the screen, as shown in .

Figure 1. Television picture caught in mid scan

If you have a digital SLR or an advanced prosumer camera that has a Shutter Priority setting, all you have to do is set the shutter speed to 1/15 of a second to solve the problem. That exposure is long enough for the television to complete a full scan cycle and render a complete picture, as shown in .

Figure 2. A complete picture of the television screen

But what if you don't have a Shutter Priority mode or some other way to set the shutter speed? Does that mean you're banned from television photography? Certainly not. You just have to get a little creative. Your success depends on fooling the camera into using a slow shutter speed. Here are a few tricks to accomplish this:

  • Set the ISO to the lowest setting, usually 50 or 100. This helps create a longer exposure, which is what you want.

  • Turn off the flash. It can't help you in any way with this type of photography.

  • Turn on the Spot Meter function, if your camera has one. That way, the camera will meter off the TV screen only and not be affected by ambient room light.

  • Mount the camera on a tripod to steady it during the exposure. The longer shutter speeds are good for preventing scan lines from the television, but they put you at risk for camera shake, which deteriorates sharpness.

  • Try to time the exposure for when there isn't a lot of movement on the screen.

  • Shoot multiple exposures. The nice thing about using a digital camera is that you don't have to worry about wasting film.

These techniques will usually render a good image of the TV screen. But if for some reason you're still getting scan lines, there are a few super-tricks you can try. If your camera has a Nighttime Mode or a Long Shutter mode, activate it. Also, get your best pair of sunglasses—neutral in color, if possible—and hold them in front of the lens. They will serve as a polarizing filter and darken the image, forcing the shutter to slow down.

TIP

Sometimes, digicam autofocus systems have a hard time focusing on television screens. Hold the shutter button halfway down until you hear the focus-confirmation beep. Then, continue pushing down to make the exposure.

TV pictures have that certain, well, television look. But for those times when you want to document a world that would otherwise be out of reach, these techniques will get the job done.


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