How to Meter When Working with a Strobe or a Flash
Learning how to meter is essential to your success when working with a strobe or a flash. But it can also be very confusion. That is because metering for artificial light is very different from metering with natural light.
Let me explain.
When it comes to metering, there are two types of readings one can take, reflective and incident.
Reflective Metering
Reflective metering measures the light that is reflecting off of your subject. This is the method used by in-camera meters, or when in Spot Meter mode on your handheld meter.
There are many benefits to reflective metering. It’s fast and convenient. And you do not need to physically place your meter next to your subject to get a reading, which makes metering for landscapes or something far away possible.
Reflective metering reads the light that is reflecting off of your subject.
The problem with Reflective Metering, however, is that it can be inconsistent.
Because Reflective Metering reads the light that is bouncing off of your subject, the reading you get will be affected by the brightness and colors your subjects are wearing, as well as the tones of their skin.
So, for example, if you are photographing a bride and groom, the bride’s white dress will reflect more light than a groom’s black tuxedo and therefore, the reflective meter reading you’ll get off the bride’s dress will be different than the reading you will get off of the groom’s tuxedo, even when both the bride and groom are standing in the same light. This would result in one or the other of them being under or overexposed.
To get around this problem, many photographers use a gray card when metering this way. A gray card is a small card that has been printed to be a perfect “middle gray” tone.
To use a gray card, you place your card in the front of the subject you are wanting to photograph and read the light that is bouncing off of it.
Using a gray card works well in most natural light settings, however it does require an extra piece of equipment (the card) and it requires that you are close enough to your subject to be able to walk up and place your card in front of them, which can be inconvenient or not possible if your subject is far away.
Also, Reflective Metering can only be used when working with natural light. When metering for strobes and flash, you will meter using the Incident Metering method.
Incident metering measures the light that is falling on your subject. When metering for artificial light, use incident metering.
Incident Metering
Incident metering measures the light that is falling onto your subject rather than the light that is reflecting off of your subject.
This is my preferred method of metering. It's easy, accurate, and consistent in all lighting situations. You don’t need to worry about having a gray card on hand. And it doesn’t matter what your subject is wearing or the tone of their skin, the only thing the meter is reading is the light that is falling on them.
To better illustrate how incident metering works, let's look at the example of our bride and groom again.
A Reflective reading will give you a different reading if you meter off of the bride’s white dress than it will if you meter off of the groom’s black tuxedo. With Incident Metering however, you will get the same reading if you meter in front of the bride's white dress as you will if you meter in front of the groom's black tuxedo. Because you are only measuring the light that is falling on them, as long as they are both standing in the same light, your readings will be the same.
The drawback to Incident meter is that it requires you are close enough to your subject to walk over and take a reading. It also requires an extra piece of equipment, a handheld light meter.
As mentioned above, Incident Metering is the only way to meter when working with strobes and flash. So when purchasing your hand held light meter, make sure that your model is equipped to take incident readings for both natural and artificial light.
Need more help?
I’ve been teaching other photographers how to create soft, natural looking light with strobes and flash since 2014! And I would love to teach you too!
You can learn more abut my method and about my signature course, The Missing Link, by watching my free informational webinar!
In this 60 minute course, you will learn how artificial light can help your brand and your business, some of the common mistakes people make when getting started, what equipment you need (and don’t need) when getting start AND exactly what I teach the students I work with inside of The Missing Link.
