You might have noticed that the image you see through your viewfinder does not always match your final image. I’m sure we’ve all had times where we think we’ve exposed an image properly and then we look down at the LCD screen and the image is far too bright or dark! Nobody wants to spend their time looking down at the screen each time their settings are adjusted. So how can you tell if the image is exposed properly BEFORE you take the shot?
When you look through the viewfinder on your camera, you will see an exposure meter on the side or bottom of the image. It indicates how exposed your image is. If the indicator is in the middle of the exposure meter (at point “0”) it is a perfect exposure. An indicator to the negative side of the exposure meter means the image is underexposed. If it it’s to the positive side, it is over exposed. Checking what your exposure meter is registering before pressing the shutter should give you a good idea of whether your settings are where they need to be.
You’ve probably gathered from the previous posts that exposure is the amount of light in the image. Put very simply, it’s how dark or bright your image looks. Exposure is measured in “stops.” Each stop is double the exposure of the stop before it, and half the exposure of the stop after it. So, increasing by one stop means that you’ve doubled the level of exposure in the image.
Aperture, shutter speed, and ISO are also measured in “stops.” (While shutter speed is measured in seconds, the speeds available on your camera often double with each setting, the same as moving up one “stop” would.) Therefore, if you increase your aperture by one stop, you can decrease one of the other parameters by a stop and still maintain the same exposure.
As you know from the last few posts in this series, the “exposure triangle” is made up of three elements: aperture, shutter speed, and ISO. Changing any of these elements will change the exposure of the image. In the last few posts, I asked you to experiment with changing one element at a time using the “aperture priority,” “shutter priority,” and “program” modes on your camera. In manual mode, you control all three elements at once. It sounds like it can be overwhelming, but once you determine what you want your final image to look like, it gets much easier!
We learned that changing the aperture, shutter speed, and ISO can create certain visual effects in the final image, such as a blurry background, stopped motion, or grain. When setting your exposure, simply determine which effects you want to achieve in your final image and then rank them from highest priority to lowest. Are you shooting portraits and want to keep a wide-open (low f-stop) aperture so that your background will be blurry? Do you shoot sports and want to make sure your shutter speed is fast enough to catch the athletes in motion? Whatever you’re shooting, pick the variable that is most important to you and set it first.
From there, move on to your next important variable and set it. Before setting the final variable, I usually check my exposure meter and see if the image is too bright or dark. This allows me to set my last variable appropriately so that the final image is well exposed.
This photo of Lauren’s engagement ring is one of my all-time favorite ring shots. For this photo, I knew that I wanted the main stone to pop out from a nice creamy background. So, I started by setting a wide aperture of f/2.8. I also knew that I didn’t want any digital noise or grain in the image, so I set the ISO to a low number of 200. At that point shutter speed was the only thing left, so I changed it until the image was exposed correctly (1/1000 sec.).
The next photo is of Elizabeth splashing in puddles at my parent’s house. I wanted a nice creamy background, so I set my aperture to f/2.0. Then I had to decided between shutter speed and ISO. Since it was a bright day, I decided to lower the ISO to 200 in order to avoid noise. Then I bumped my shutter as high as it could go while keeping a good exposure, so that I could capture the water splashing (final shutter speed = 1/3200 sec.).
As you can tell, I generally start with aperture, because I just LOVE when the background is smooth. After that I generally toggle back and forth between ISO and shutter speed. I like to keep the ISO as low as possible to avoid noise, so that’s generally the second parameter I set. Usually my ISO is a constant 200 unless I’m shooting at night or in a dark room where I really need the extra light sensitivity. For shutter speed, I try to avoid going slower than 1/200 sec. at all times, just to be sure that I won’t get any camera shake. Since my ISO is usually around 200, I can generally increase my shutter speed pretty high before the image starts looking dark. This works out to my advantage, since a lot of my subjects are children who are running around!