Exposure is the amount of light that reaches your camera’s sensor, creating visual data over a period of time. To get the correct exposure is an art in itself.
Sofia leads this weeks challenge. Here is her entry.
So are you wondering how to get the perfect exposure? Have you ever heard of the exposure triangle? There are three elements: Aperture, Shutter Speed and ISO. These three work together depending on what you are shooting to get the exposure just right. There are pros and cons of the extreme ends of them all and sometimes in bad lighting conditions you have to pick what you’re willing to sacrifice.
First let’s talk aperture. The aperture is the opening of the lens. The wider open (lower aperture number) the more light gets in your camera; the larger the aperture number the less light gets in. If you have a camera with a kit lens, it is more than likely a variable aperture lens. This means that at the shortest end of the zoom it has one aperture (the lowest possible aperture number for the lens) and then as you zoom in the aperture number gets higher. There are also prime and zoom lenses that have a fixed aperture. The aperture is measured in f-stops. If you have a lens with a variable aperture of 3.5-5.6, the lowest aperture it is capable of is f 3.5 at its shortest zoom distance and 5.6 at its most zoomed in point. As you zoom in, the lens is limiting the amount of light that gets into the sensor. There are also lenses with fixed apertures, some as low as f 1.2. These fixed aperture lenses are more expensive, but in my opinion are well worth the investment, especially if you are going to be shooting in low light. However, the lower the aperture, the smaller the depth of field…this is where you have to look at what your goal is. Depth of field is the amount of the photo that is in focus. For example, if you shoot at f 1.8 and are focused on a person’s eye, his/her nose might be out of focus. You have to evaluate what is more important; the depth of field or the amount of light getting in your camera. This is just one decision to make when determining your exposure. Now let’s look at shutter speed.
What is shutter speed? It is how long your shutter is open to capture the image on the sensor. The shutter speed can range from bulb, where you can leave the shutter open as long as you’d like, to very fast speeds, such as 1/4000th of a second. A general rule of thumb if you’re hand-holding the camera is, if you are shooting with a 50 mm lens, you need to shoot at a shutter speed of at least 1/50th of a second. If you are shooting with a 300mm, then you need 1/300th of a second. If your camera is mounted on a tripod, then you don’t really have to think about this. The key to shutter speed is what you are shooting. If you are shooting something that is still, you can shoot at low shutter speeds to allow more light in, but if you are shooting action, you need a fast shutter speed. I try to shoot sports at 1/1000th or faster. If you are outside, then this is not an issue, but if you are shooting indoors, this can be a limiting factor. For example, if you are shooting outside during high sun hours, you might have to shoot at an even higher rate so you don’t over expose your photo.
The last thing I look at is the ISO. The lower the ISO, the less sensitive the sensor is to light. At ISO of 100, the sensor is less sensitive to light or, on the higher side, an ISO of 6400 will make your sensor very sensitive to light and will “allow” more light to be captured on your image. If your lighting is just right and you can shoot at ISO of 100 or 200, do it because this is where the least amount of digital noise (white looking specks on your image) will be introduced. The higher your ISO, the more digital noise that will be introduced into your image. When I shoot indoor volleyball matches, the lighting is really low, so I have to shoot at high ISOs in order to be able to shoot at shutter speeds fast enough to catch the action. For example, for most volleyball matches, I shoot at 1/1000th, f 2.8 and ISO 6400.
Now to put all this together: Your camera has a built in light meter. It should read something like this
The camera’s proper exposure is when it measures in the middle at zero. I would start there and then adjust one of the 3 elements at a time until you reach your desired exposure.
What makes photography a strange invention is that its primary raw materials are time and light.John Berger
You can use long exposures (long shutter speed) to create silky water or light trails. You can use a short exposure (fast shutter speed) to freeze action. I am a sucker for both very long exposures and short ones as well; I enjoy capturing light trails, waterfalls, and sports action.
A snapshot steals life that it cannot return. A long exposure [creates] a form that never existed.Dieter Appelt
Long Exposure Captures
Taking pictures is savoring life intensely ever hundredth of a second.Mark Riboud
Did you know that you can capture a long exposure photo on the current iPhones? Want to know how?
Be sure to take a Live Photo of your flowing water, while stabilizing your iPhone. Once you have your Live Photo, watch the video below on how to make it look like it was taken on a camera with a long exposure! Perfect trick if your out and about with only your iPhone!
Be sure to check out this Post!!