Just what the title says! What if you don’t have time to line up a grey chart but want some kind of reference for correct exposure through all your shots?
Here are three ways (and a bonus tip) on how to use your hand as a light meter for run and gun productions, as well as lighting sets. Enjoy:
Just in case it isn’t clear: You measure for the key side, not the fill or shadow side. You also avoid specular highlights. In the video I’m leaving about 5 IRE off the top to average out skin tones.
In a nutshell:
Method 1: Use the palm.
You use the palm for accurate exposure after calibrating it with a grey chart. You only have to do this once. I don’t recommend this method because you’ll always have to step into your scene to judge exposure and it’s not practical.
Method 2: Use the back of your hand.
This is similar to using the palm, but is more favored because it gives a better ‘reading’ of skin tones. Again, you don’t use it much for exposure, but for general walking around the set to check how light reacts to your skin. Once you build up a memory of your skin tone it’s a good indicator of exposure.
With today’s exposure tools this isn’t that useful, but if you don’t have a light meter then it’s better than nothing!
Method 3: Use the back of your subject’s hand
This is more useful and practical. You calibrate your subject’s hand with a grey chart and then as long as you have a waveform monitor or false color tool you can accurately nail exposure every single time.
- Get your subject to hold his/her hand next to a grey chart at the beginning of your shoot
- Make sure both are lit evenly and with the light source equidistant. If the light source is to one side there will be fall-off and you won’t get an accurate reading. You can also put it on top of each other so they occupy the exact same spot.
- Expose for middle grey. With strict Rec. 709, it’s at about 45 IRE. Modern cameras can do a whole lot better, which is why 50 IRE is a good base standard. If you’re shooting log, the value changes. E.g., for the Panasonic GH5, it’s at 41 IRE.
- Compare the skin tone to the middle grey chart. In the above video both fall at about 50 IRE. So I can, in effect, use the back of my hand as a middle grey chart. The subject’s skin tones will vary of course, so note that.
- Just maintain this exposure (or under or overexposure, based on your tastes) throughout the shoot! Your skin tones will all line up perfectly.