Travel Photography Tip: Exposure Locking + Metering Modes

Often the source of this problem is an incorrect meter reading, which leads to an incorrect exposure. “Metering” is your camera’s ability to determine how much light is available for a scene. Back when working with film, photographers often physically walked up to their subject with a handheld light meter and took a reading. It literally measured the percentage of light reflecting off the subject.

These days we’re mostly digital, and in that split second between the act of pointing and the act of shooting, digital in-camera meters read the amount of light and select the best settings for you (unless you’re on Manual). Brilliant, right? Well, not always. Often, what the camera decides is best for the entire scene is not best for your subject — leaving it too dark, or blown out, or simply “flat” and lifeless.

Exposure locking

A good step, then, is to learn to use the Auto-Exposure Lock button. This is useful in all semi-manual modes (Program, Aperture Priority, and Shutter Priority — it will do nothing on Manual). What this button allows you to do is point your camera at your subject, or at the brightest area that’s at risk of being blown out (or really, whatever area of the image you want most correctly exposed) and get an exposure reading for that area (meaning it will select whatever settings you haven’t yet). You then press your shutter halfway, hit your AE Lock button, and recompose your shot. Recomposing means holding the settings for what you want correctly exposed, but returning to the original composition you were planning.

An example would be a friend in front of an ocean scene. Sometimes, the face will be rendered too dark in order to expose the ocean. So you could take a reading from the face, lock those settings, and then recompose to include the ocean. The ocean may come out a bit brighter, but the face should be correct. Of course, not every scene can translate to a perfect exposure. In this scenario, it’s likely that the sky will be washed out in order to expose the face.

You’ll know you’ve locked the exposure setting on a Canon when you see an asterisk in the viewfinder; on a Nikon it will read “AE-L.” To hold the settings, keep the button depressed. If you want to take new settings, release, wait about 5 seconds, and it will begin reading the scene again (you can watch the numbers change as you move your camera around). Otherwise, recompose and finish depressing the shutter completely.

This “trick” should explain why you might see photographers pointing their cameras in (seemingly) all directions, before settling back on the subject or scene at hand: They’re taking a reading for a correct exposure.

Metering modes

The metering mode you’re using will determine how accurate your reading is. The more accurate, the better the chance of getting the exposure you’re hoping for; however, this carries with it a greater chance for error should you meter incorrectly.

There are four metering modes on most DSLRs:

Evaluative metering

Centre-weighted metering

Partial or spot metering

The same scene, just a moment later. The camera was switched to partial metering, and I metered just left of the sun. This sped up the shutter speed, because the camera thought it was a very bright scene. I locked my exposure, recomposed, and took the shot. This created the silhouettes I was hoping for, while capturing maximum colour in the sky.

In order to fully grasp these options, it’s best to just head out and try them all.

• Practice using the AE Lock button and recomposing the image.
• Expose off of different parts of the image and compare results.
• Play around with creative exposures, such as silhouettes, creatively under- or overexposed portraits, etc.
• On a sunny day, go to the park or beach. In one photo, take an exposure reading directly off of the sky. Lock, recompose, and shoot. In a second photo, take a reading off of the grass. Lock, recompose, and shoot. How do the pictures compare? Which do you prefer?
• Pick any scene and try shooting it in each of the metering modes. Which mode best suited the scene?
• Place an object on a table by a window, allowing it to be back-lit or side-lit. Run through each of the metering modes. Which produced the best exposure?

It’s best to understand how to take meter readings in semi-manual modes before moving on to full manual exposures. Once you’ve mastered Aperture and Shutter Priority, have a good understanding of the exposure triangle, and finally, have a grasp on exposure options, you’re then probably ready to head into fully manual shooting.

If you’re not quite there yet, rest assured that it’s far better to understand each of these elements than to just shoot blindly in Manual hoping for the best. It’s not easy and it certainly takes a lot of time and practice.

Keep learning! Check out the curriculum for the MatadorU Travel Photography program.