Lighting: Making video in Low Light Conditions

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Jeff Sengstack, September 2009.






Newer camcorders are becoming more forgiving in low-light conditions. As a result, using a few creative tricks, your work can show a cut above the competition.

You know the drill: lights add sparkle, improve contrast and enhance colors. But you also know that there are times when switching on all the lights in a room or putting a couple of studio lights with umbrellas in the corners will destroy the moment or just take too darn long to be worth the effort. It's become a lot easier for videographers to grab romantic or touching moments without intrusive, glaring lights. Eventually, if not already, you'll find yourself shooting in low-light conditions.

Rather than use your camcorder's infrared mode and light with its lovely green glow, you should consider taking a few other steps to ensure your video quality is as good as it can be in low-light conditions. Despite that relative ease of use, there are some steps you can take to ensure your shots are a cut above the competition.

Low-Light Issues

There are several issues that arise in low-light conditions:

  • Video noise. This is a result of using extra gain, either via the auto gain control or manually increasing gain. Increasing gain is like using high-speed film. In film, the chemical granules are larger so they can absorb more light, but that leads to grainy-looking images. Video gain uses electronic amplification, which can lead to similar grainy results with static thrown in for good measure.
  • Streaking. If there are bright spots in your low-light setting, such as candles, small lights or reflections, panning or zooming leads to streaks as the after-image of those hot spots linger in your image.
  • Blurred motion. If you use a too-slow shutter speed to compensate for the low lighting, any motion - camera movement or action in the frame - will look blurry.
  • Poor focus. Manually finding a focus in low-light conditions can be a problem, and your camcorder's autofocus might not be able to "see" a subject.
  • The spotlight look. To compensate for low-light conditions, some videographers use an on-board spotlight. That can be fine to use for fill, but when there is no other lighting, it can create a sharp-edged, annoying-looking circle of light.

There are easy ways to overcome low-light issues. Here are some basic tips:

Switch to Manual:


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  • Do not use Automatic Gain Control (Figure 1). If you leave AGC on and the lighting changes or subjects move closer to or farther from the camcorder, you'll get fluctuating gain levels.
  • If you can manually adjust the gain on your camcorder, increase the gain. +3dB is equivalent to opening your lens about one f-stop. Depending on your camcorder, a setting greater than +6dB (more than 2 f-stops) generally leads to too much video noise.
  • Reduce the shutter speed. The auto shutter speed on many camcorders has a 1/60 second bottom limit. If you have manual shutter speed control, reduce your speed to 1/30 of a second. If you drop the shutter speed to less than 1/30 of a second, any motion, zooms or pans will have smearing or create streaks of light.

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  • Don't use autofocus. Many camcorders use a passive autofocus system that needs light and contrast to set the focus. Low-light conditions typically fool the camcorder to use improper focal points or make slow focus changes. If there are flickering lights or candles (Figure 2), autofocus might continuously shift to try to follow the moving light.
  • Set your focus and leave it. Find a stationary subject in the scene, zoom in tight, manually adjust the focus, zoom out and then leave the focus alone.
  • If there is action and it's too difficult to find or change focus, focus at about the distance of the action (check the distance on the focus ring), zoom out and stay wide. If the action is steadily coming toward you or away from you, then gradually rotate the focus ring clockwise (closer focus) or counterclockwise (more distant), without fretting over getting the focus absolutely correct.



More Low-Light Shooting Tips:
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  • Use a tripod or find some other way to make your camcorder rock steady (put it on the floor or a table).
  • Don't use filters - internal or external (Figure 1). They decrease the amount of light getting to the video chips.
  • Zoom out all the way and stay zoomed out throughout the shoot. That lets in more light.
  • Better than simply zooming out is to use a wide angle lens and zoom out. If your camcorder has a 2x extender, set it to 1x.
  • If your camcorder supports pre-sets, Google your camcorder's make and model and see what other videographers recommend for low-light conditions.
  • If you use an on-camera light, get one that can be dimmed or that has barn doors and then use a diffusion filter (Figure 3) to avoid the spotlight and squinty-eyed look.
  • Look for silhouettes. They can be in front of something like stained-glass windows (Figure 4). Or back-light subjects to create powerful emotional content.
  • Add lights without wrecking the mood. If you have studio lights, use barn doors to create spotlights that you can use to illuminate static subjects. If a subject is in the background, that will add depth to your shot. You can also place lights behind and below subjects to create silhouettes without lighting the entire scene. Basically, your goal is to find some unobtrusive way to illuminate items in the scene where full lighting wouldn't work.
  • If you must shoot outside at night with minimal lighting, see if you can schedule the shoot when the moon is full. And remember, for color-balancing purposes, a full moon is reflected sunlight.

Get Good Lux

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If you're in the market for a camcorder, consider its lux rating. Lux is a measure of a camcorder's low-light capabilities. The lower the number, the better. For example, a camcorder with a lux of 10 won't work well in low-light conditions, while a lux of 2 will likely handle most low-light conditions.

The thing is, most camcorders these days have good low-light capabilities. In addition, lux is not a true standard with hard and fast testing procedures. Lux lends itself to marketing hype.

That said, a camcorder with a lux of .2 (two-tenths) can shoot in darn near total darkness. A camcorder with a lux greater than 4 probably will not work well in seriously low light. Because lux values are an inexact science, it's probably best if you try out a few camcorders in low-light conditions before you make your purchase.

Create a Competitive Edge

To gain an advantage in the marketplace, you need to set your work apart from the competition. Working effectively and creatively in low-light situations can enhance the mood of the moment, improve the overall quality of your productions and please your clients.

Jeff Sengstack is a video producer, an Adobe Certified Expert in Premiere Pro and Photoshop, author of three books on Adobe Premiere, a former TV news reporter and a junior college computer science instructor. He recently completed a video tutorial for lynda.com on Premiere Elements 7, the consumer-level video editor from Adobe. 


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