OK, that post title might be a slight over exaggeration.
But what I’m sharing with you today is the key to gaining control over your camera and the images you want to create.
I remember when I got my first dSLR and I tried SO HARD to understand what would make an image dark versus too light. I read up for hours on the internet and I studied “exposure tables” (because I’m a nerd like that) to try and predict what settings I’d need to create the right image – where ever I happened to be.
I remember being SO FRUSTRATED when I would manually choose my settings (my shutter speed and my aperture) and then looking through the viewfinder always to see that little needle buried to the left, indicating a grossly underexposed image. I didn’t get it. I knew I could lighten it up in Lightroom. Why was my camera telling me my image was underexposed? (Actually, this is because I didn’t totally how the understand the exposure triangle worked.)
Your camera’s best kept secret!
But the point of my little story is not my frustration in underexposed images. It’s the camera’s built in light meter.
Back in the day, people did have to memorize tables or carry around external light meters, but today all dSLR cameras come equipped with one built right in.
Now you’re probably thinking this is kind of lame for a “best kept secret.”
But get this – by using your camera’s light meter, you can nail exposure of your image. Every. Single. Time.
Understanding how, when and where to expose in a scene can drastically improve the quality of your images and cut down on your edit time!
Why do you want to nail exposure?
Creating a beautifully exposed image straight in the camera is the fastest, cleanest and easiest way to end up with a beautiful image on your walls (or on your computer, if that’s your taste).
I’m all about saving time AND creating amazing images. That’s why you want to get your exposure correct in the camera.
How can you control your camera to get a correct exposure?
It’s called metering and you use your camera’s light meter to determine correct exposure.
Image Credit: www.imaging-resource.com
Professionals step back here please. This post is intended to help aspiring photographers understand how they can easily determine the correct exposure for a scene. It is not meant to replace your expensive light meters nor suggest that additional lighting is never needed.
1) Know how you want the camera to determine exposure (spot, matrix (average), partial, etc).
The camera has different ways of reading a scene and determining correct exposure. Knowing when to use each can help you obtain your desired exposure in the camera.
Canon metering modes
On a Canon 7D, (which is what I use) the different metering modes are: Evaluative, Partial, Spot and Center-weighted average. Their names are fairly self explanatory, but I’ll dive into each one a bit more here.
Evaluative/Matrix mode:
By default your camera is likely set to evaluative or matrix mode (Canon or Nikon). This will be totally fine for almost all of your photographs. What the camera does is break the scene up into different zones and “evaluates” the light in each “zone.” Then it decides on what “proper” exposure should be, based on all that information. It attempts to find a middle grey and even out the light in a scene. For most lighting situations, this works perfectly fine.
The actual algorithms are super top secret, never shared with anyone, and vary between manufacturers as well as between camera models. And it’s probably TMI anyways. (But if you’re really interested, you should read this article on Evaluative Metering over at Digital Photography School. Super interesting!)
Partial:
Instead of using the whole scene, your camera uses about 20% of the center area to determine correct exposure.
Spot:
This is even more “precise” than partial metering. Now your camera only uses about 2% of the scene to determine correct exposure. By default, this is the center focus point, but some cameras have the ability to set the spot meter based on the active focus point.
Center-weighted average:
This is very similar to evaluative metering except than the camera places more weight on what is in the center of your scene. (Apparently it is an older technology that was replaced by the evaluative metering mode.)
When would you want to use other metering methods?
This is personal preference, but I rarely switch out of evaluative. Once you begin to understand how your camera works and how it determines exposure, you can compensate for it and adjust accordingly. It’s just one less button/setting to adjust for.
However, the other metering modes do have their uses.
When I photographed people in my studio on a black background, I used spot metering, and sometime partial metering (depending on what was going on in the scene). If I used evaluative, my images would come out too bright, because the camera would try to compensate for all that blackness in the background. By using spot metering, I could focus on my subject and my camera would only use that information to determine the correct exposure. This article from Digital Camera world explains exactly how to use spot metering.
Partial metering is great for backlit subjects as well. You can “meter” off of your subjects and the rest of the scene is ignored. That way your camera doesn’t try to include the bright background in it’s determination of correct exposure.
2) Know what area of your photograph you want to expose for
Your camera is only as smart as you tell it to be. It will get exposure right in most lighting situations, but sometimes the light will be too tricky.
If you’re trying to create a silhouette, you’ll need to expose for your background, not your subject. If you’re trying to photograph a subject on a bright background, you need to expose for the subject. Check out the images below, when I was attempting to take some self portraits during my last pregnancy. (I ended up getting my 5 year old’s help…he loved using the wireless remote trigger, which you can plainly see in the images below!)
If you left your camera in evaluative mode, you’d get basically the top image.
I bumped up what my camera was telling me to +1 over exposure and got the resulting middle image.
The bottom image is a tiny bump more (which I judged by looking at my screen AND the histogram), and then I added some contrast when editing.
3) Learn how to “out think” your camera
When you’re in a semi-automatic mode, you can use Exposure Compensation to “trick” your camera into “overexposing” the scene. If you don’t photograph in RAW just yet, this can be a life saver for nailing your exposure.
When you’re in manual mode, you adjust your settings to bump up your exposure manually.
This is the great thing about digital photography – you get instant feedback. Practice makes perfect. So if it’s not right the first time, adjust your settings until it is!
Here’s another example of how you can use exposure compensation to achieve the correct exposure:
Both images are Straight out of the Camera. The first image is what the camera told me was a correct exposure. It is incorporating the brighter spots in the background and results in an underexposed subject. The bottom image, I simply adjusted my exposure by +2/3. (So my camera was now telling me my image would be overexposed by 2/3.) By reading the histogram on my camera, I determined otherwise.