Lighting: Lighten up your world with LEDs

vm_logoTerry O'Rourke, 2011


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If you're just starting out in video production and are looking to get some lighting kits, things can get quite confusing - and expensive - very quickly.

The selection of lighting fixtures can be overwhelming and the pros and cons of each choice can also be daunting. With this in mind, it's best to maintain an open mind when considering which technology you will choose to work with. Today we are going to take a look at LED technology and how to fit it into your video production world.

LEDs (light emitting diodes) are all the rage today and for good reason, they provide a wonderful way for the videographer to use artificial lighting just about anywhere one could imagine. Among other qualities, they are light in weight, reasonably powerful, energy efficient - which is perfect for running on batteries - and cost effective. But most of all, they run cool so you can use them all day without heating things up. Did I mention perfect color balance in your choice of 5600k or 3200k, or both for that matter? Or how about dimmable? Oh I forgot reliable too - LEDs can have a life span of up to 100,000 hours. Sound good doesn't it? So why should you consider anything else: compact size, reliable, runs cool, good color balance, dimmable, I guess we're done - just buy a bunch of LEDs and start shooting!

But wait, it's not that simple. (It never is though, is it?) LEDs are everything I mentioned and more, but they lack something. Just like meeting that perfect person or landing that perfect job; after a while you begin to feel something is missing and eventually you realize it's "that something special", that spark. Yep, nobody's perfect and LEDs are no exception. So let's peel away all the hype, get to the heart of the matter and find out what they really are... aside from being nearly perfect that is.

Can We Talk?

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With all that perfection comes some pretty boring qualities. Take shadows for instance. If placed correctly and used with a simple fill card, LEDs can provide nearly shadowless lighting which is perfect in situations like closeup interview lighting or product lighting where you might not want hard shadows to accentuate flaws. That's the thing about LEDs, they don't put out "directional" or focused light which is needed for well-defined shadows. So if the scene you are painting needs a little drama with hard shadows, LEDs might not be the way to go.



Bad Stuff

In previous articles, we've discussed how to create shadows by moving your light source farther away from the subject. This is common knowledge among lighting directors and is a handy way to shape the quality of just about any light, even LEDs. The problem is when you increase the distance between your subject and the light source to create shadows, you also increase the amount of power required for achieving the same output of light. This is where LEDs can fall short, because the same quality that gives LEDs that wonderful soft light also conspires to defeat your efforts to create hard shadows. LEDs, by their own nature, provide soft, non-directional light which is diffused much like that from a soft-box. That diffused nature also limits the throw of the light. The throw of a light fixture is its ability to project light. A follow spot used for stage productions throws light all the way across the theater. A diffused light such as from an LED has very little throw, so moving it back from the subject can be impractical because that decreases the amount of light reaching your subject. This is called light fall-off. Without going into the math; you need to double the light output going from 2 to 4 feet and quadruple it at 8 feet and so on (unless you focus the light). With all this in mind, unless you have several LED banks, they can be a bit frustrating when used in large environments at long distances such as in lighting large rooms with multiple subjects, because they don't have a lot of output at greater distances.

Good Stuff

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When lighting interview subjects in a room, it's sometimes best to light the subjects while isolating them from the background. LEDs are perfect for this. You can put them close and record all day because they run cool and that wonderful soft quality gives you fantastic results. Since they have rapid light fall-off you don't have to worry about your light spilling all over the room. However, this soft lighting can be pretty mushy unless you provide a bit of rim lighting around your subject. In a situation like this you might want to consider a hair light. You can do this with a fixture that has a narrow beam of light so it won't spill all over the set. It needs to provide sufficient throw because it's going to be far enough away to be out of the set and powerful enough to provide that nice rim light. A small fixture pointing down from above, mounted on a boom stand is the best way to do this. It should be small, for safety, because it's on a boom.

The best way to control the spill of a small light and to increase its throw is to attach a focusing modifier such as a fresnel or spot. Not only do these modifiers increase the light output by increasing the throw they also control spill and create wonderful, controllable hard edged shadows. The only problem is, you can't effectively use them on LEDs. Nor can you attach simple reflectors such as snoots or grids; both cost effective ways to achieve narrow light sources and well controlled hard shadows.

LED Pros and Cons

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There's a lot of good and bad for everything we use. Regardless of what some clothing manufacturers might want us to think, there's no such thing as 'One Size Fits All' nor do we all fit into the ubiquitous 3 sizes only: Small, Medium and Large. Ask a robust short woman or a very tall thin man, they can tell you how difficult clothing shopping is, and the same goes for video equipment gear. This is very clear with production lights, even more so because all of our needs differ, depending on how we use them, how long we use them, where we use them, and what we're shooting. However, we're discussing LEDs, and there are some good and bad points to this lighting technology. Here's a list of most of the pros and cons to LED use in video:


Pros:

  • Reliable long-lasting bulbs.
  • Very consistent color output whether you use 5600k or 3200k units.
  • Dimmable and maintains consistent color at any setting.
  • Very low wattage consumption. Excellent for battery life for portable on-camera use.
  • Very low operating temperature. Great for using gels because the lights won't melt the material.
  • Available with both 5600k or 3200k bulbs in the same unit.
  • Compact and light weight.

Cons:

  • Can be expensive for the amount of total usable light output.
  • Limited use with modifiers like snoots, reflectors and grids.
  • No fresnels or spots.
  • Limited control of shadows.
  • Very rapid light falloff (limited throw).
  • Limited use in large environments.

Many of the qualities that make LEDs so attractive for taping video also limit their application in situations you may frequently encounter in your day to day operations. They have their place in you kit but you must consider other, more controllable lights as well.

Terry O'Rourke specializes in retail advertising photography and videography for clients worldwide.


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