So what the heck is this thing? Listen there are two types of people in the world, if you’re the kind that has one of these gathering dust in your camera bag and you should watch this tip! If you have no idea what this is, then you should watch this tip! So this thing is called a light meter. To understand how light meters work you need to know a little bit about how light works. No matter which direction it’s coming from, light eventually hits your subject, and then bounces right off when you take a picture! The meter inside your camera reads the amount of light that’s reflecting off your subject, and hitting the camera sensor. An external light meter reads the incident light. That tells you exactly how much light is hitting in the first place, and it’s not influenced by the reflected light, so who cares? Well you probably learned in elementary school, that different colors absorb and reflect different amounts of light! So even though the same amount of light might be hitting a black wall and a white wall, they reflect different amounts of light back. I can prove this by zooming in on a dark area of this wall, and taking a picture on shutter priority using 400 ISO at 1/80th
of a second. The cameras meter is calibrated to what’s called 18% gray, which is a neutral light grey color. So it reads the light reflecting, and will want to lighten the dark wall to make it grey! The aperture it selects is f/5.6 at the same time. if I shoot a bright part of the wall, the camera also wants to make it the same color gray. So it closes down the aperture all the way to f/16 to darken the bright wall. The problem is that I want the dark wall to stay dark, and the bright wall to stay bright. I want it to look exactly like it does to my eye by using an incident light meter! I can measure the actual amount of light that’s hitting the wall in the first place. It doesn’t look at the reflected light at all, so it doesn’t know or care a bright or dark the wall is. I can set my light meter using the same two numbers that I used in my camera. 400 ISO at 1/80th of a second, and it tells me the aperture should be f/10. now I can set my camera manually, and see that the dark wall is dark, and the bright wall is bright, just like they should be. Now look, I know you can eyeball your exposure on the camera screen, and adjust, but it’s hard to see in bright daylight, and those aren’t always super-accurate, because those screens are made to be punchy, contrasting and saturated, so everything looks really good, so by learning to use an incident light meter you can have total control over your exposures, and prevent your camera’s meter from being fooled too easily! Hey don’t forget that I’ve got new Two Minute Tip video every Monday at 11 o’clock Eastern so punch that subscribe button down there, and you won’t miss anything, including a bunch of other free photo shows from my friends at AdoramaTV!