Take a picture of a computer screen can be surprisingly challenging. Between glare, reflections, blur, and those weird lines that can break up your image, it's easy to get overwhelmed and discouraged. The good news is there are some specific steps that can help make your photo a success, whether you're using a digital camera, a cell phone, or even the computer itself.
Using a Digital Camera to Photograph a Computer
You can use a point-and-shoot camera or a DSLR to take a photo of your screen. Either way, it helps to know how to change the setting in your camera.
1. Determine Your Screen's Refresh Rate
These days, most computers feature LCD screens, but there are some older monitors that may still have CRT technology. Both kinds of screens have a refresh rate, the rate at which the entire picture refreshes on the screen. You can't see this with your eyes, at least if it's properly adjusted, but your camera can see it, resulting in dark bands or blank sections of the screen.
In the case of bulky old CRT monitors, the refresh rate is usually at least 60 times per second. If the shutter speed on your camera is faster than the refresh rate, you risk capturing part or even none of the image. A similar thing can happen with LCD screens as the pixels refresh, often creating a herringbone pattern. However, LCDs often have a faster refresh rate. This allows for a faster shutter speed.
If possible, look up the refresh rate in your manual. If you know the refresh rate, you can determine your maximum shutter speed.
2. Choose Your Camera Settings
It's possible to get a good shot of a screen in auto mode, but for best results, you'll need to control some or all of your camera settings. If your camera has a shutter priority setting, this is the time to use it. That way, you can set the shutter speed and ISO and allow the camera to choose the aperture. If you don't have this mode, shoot the scene in manual.
- Shutter speed - Your shutter speed should be slow enough to allow the screen to refresh at least a couple of times. If you know what the refresh rate is, you can use that number. If you don't know the refresh rate, simply set the shutter to 1/30 second or 1/15 second. This way, the entire image will appear on the screen two or more times while the shutter is open.
- ISO - Set the ISO based on the available light. Since you are photographing something quite bright, you'll likely have a low ISO. Try ISO 100 or 200 and if you need more light, move up from there. Remember, the higher the ISO, the more digital noise your are introducing to your image.
- Aperture - If you're shooting in shutter priority, your camera will set the aperture for you. If not, adjust the aperture to get the proper exposure for your image using the camera's light meter.
- Flash - Turn off the flash. You're photographing something bright, so you don't need the extra light. What's more, it will create unsightly glare and reflections on the screen. The same goes for other lights in the room; turn off all the lights you can.
3. Stabilize Your Camera
For this kind of shot, you'll likely be using a slow shutter speed. In general, hand-holding a camera doesn't provide great results at slow shutter speeds. That's because you are moving slightly as you push the shutter button, creating blur and camera shake.
- Ideally, use a tripod for this shot. Even better, add a remote shutter release or use your camera's self timer. That way, there won't be any shaking as you push the shutter button.
- If you don't have a tripod handy or don't have room to set one up, try a stack of books, a chair, or any handy object.
- If you must hand-hold the camera, try to make yourself as stable as possible. Lean against a wall or doorframe and place your feet about hip-width apart with your weight distributed evenly. Tuck your elbows in against your body and breathe slowly and evenly. Shoot between your breaths.
4. Experiment With Distance
Depending on the focal length of your lens, you should experiment with taking the photo at various distances. You may notice there is a subtle banded pattern over the image of the screen. This is called "moire," and it's a common problem with this type of shot. You can minimize it by taking the photo at a few different distances. Try three feet, four feet, and five feet if your equipment and space allow.
If you are running into problems with moire, you can also try adjusting the angle of your shot. Very slightly tip the camera up or down or try taking a half step to one side or the other. The beauty of digital is you can try lots of things to get the perfect shot.
5. Choose Your Focus
Sometimes, autofocus can struggle in really bright situations. If you're trying to focus on the screen itself and ending up with blurry shots, there are a couple of ways to fix the problem.
- Focus on the very edge of the screen where it meets the frame or the body of the monitor. This is a high contrast area, which is very helpful if your autofocus is struggling.
- Switch to manual focus. If your camera allows you to use manual focus, you can rely on your own judgement instead of the camera to make sure your shot is sharp.
Tips for Using a Phone to Photograph a Screen
For the most part, your cell phone camera should function in a similar way to a standard digital camera. However, the following phone-specific tips can help:
- Adjust your phone's camera settings if you are able. Ideally, you should control the shutter speed, setting it to about 1/30 second.
- Do not zoom in to frame the shot. Zooming can degrade the quality of your shot, so in a tricky situation like this, you're best "zooming with your feet." Move yourself forward or backward to get the shot you want.
- Find a hard surface for your phone. Prop it so you have the angle you want and can frame the photo as you have in mind. If you have to hold the phone, make sure you are resting your hands on something to steady them.
- Use your phone's self timer for the shot. That way, you won't be readjusting the angle or shaking the camera as you move your finger off the button.
Using Screen Capture
One of the simplest and most effective ways to create a digital image of your computer screen doesn't involve using your camera. Both major computer platforms, Windows and Mac OS, allow you to capture an image of the computer screen with a few simple keystrokes. You can then save the file to your hard drive where you can import it into an image-editing program and modify it.
If your computer is running Mac OS, you have several options for creating a digital file from your computer screen. The following list contains different key combinations you can employ to capture all or part of what you see. The command key is often called the Apple key, and is the key immediately to the left and right of the space bar.
- Entire screen - Hold down "Command-Shift-3" to capture the entire screen. You'll hear a click, and the file will appear on your desktop.
- Selected part of screen - Hold down "Command-Shift-4" to select the area of the screen you would like to capture. Crosshairs will appear, and you can drag those to select the area you want to capture. When you let up on the mouse, the file is saved to your desktop.
- Selected window - Hold down "Command-Shift-4", hit the space bar, and select a window. You'll hear a click, and the image will appear as a file on your desktop.
The process on a Windows computer is a bit more involved, but follows the same general principles. With either method, the file is copied to your clipboard, not saved to the desktop. You can then paste the image from your clipboard into an image-editing program. Once the image is in the image-editing program, you can crop it or alter it in any way.
- Entire screen - Press the "PrtScn" key. This copies the entire screen to your keyboard.
- Selected window - Press the "PrtScn" key and hold down the "Alt" key at the same time. This captures only the active window.
You can also use third party software options and widgets to capture the image on your computer screen. There are lots of programs to choose from, including the following:
- Grab - This is a widget that comes with MacOS. You can find it in the Utilities folder. Use it to capture part or all of your screen or to perform a timed screen capture.
- Screenshot Plus - This program allows you to set a timer for your screenshot so you can set up the screen exactly the way you want. It's a free program for the Mac OS.
- Greenshot - A similar free option for Windows is Greenshot. You can use it to capture all or part of a screen, or you can even take a screenshot of a scrolling web page.
Take Your Time
The key to getting a good photograph of a computer screen is making sure you understand how your camera works and taking the time to set it up properly. That way, you can avoid blurry shots and weird patterns, allowing you to capture the important information on the screen.