Photography basics, an introduction to ISO, Shutter Speed and Aperture! These three basic elements together will determine the exposure, or how dark or light your photo, will be. If you are thinking about buying a camera for your next trip, especially a DSLR, you should take the time to learn how a camera works, and what you can actually do with it! This first of a new series of Photography Basics, we will get more into depth of the must know photography knowledge if you want to step up your game. Yes, you can buy a simple point and shoot camera, or just use your iPhone, but if you want pictures worthy of hanging on your walls, your photography 101 education will start right here!
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If we would compare the lens of a camera to the human eye, the aperture of the lens would be the same as the pupil of your eye. As you might know, the pupil of the eye changes with the amount of light available, the aperture of a camera is used for exactly that. The aperture, can be manually changed and allows light to travel through the lens into your camera body. Aperture is also known as F-number or F-stops, and this is how you will find them on your camera. In the manual settings you will find an F2.8 or an F22 for example. Let’s dig a bit deeper into how aperture actually works.
Now, this might be a bit confusing, but the larger the aperture of the lens is (or the wider open the lens is), the smaller the F number is. And not only does it determine the amount of light that travels through the camera, it also determines the depth of field (the blurriness of the background), and this is what you will mainly focus on when determining which F-stop to use. Here are some key rules you might want to remember:
- The larger the aperture, the more light will enter the camera lens; the smaller the F-stop, for example F2.8 and the more shallow the depth of field. This, in combination with the right focus, can result in a blurry background. Therefore you will most likely want to use this for portraits and close ups. However, since a large aperture allows more light to travel through the lens, you will also want to use this for night photography.
- The smaller the aperture, the larger the F-stop, for example F16, the deeper the depth of field is. This will result in all items in the photography in focus. You will most likely want to use smaller apertures for landscape photography to get a sharp image.
Still a bit confused, this video by Apalapse should explain it all!
While shutter speed is a very basic component of exposure, it still has a large effect on your photography. Shutter speed is the amount of time light will fall onto your camera sensor. When the mirror if your DSLR moves upwards, the lens will allow light to fall onto the sensor of your camera, the longer the shutter speed, the more light will fall onto your camera. Should you have a very low shutter speed, such as 1 second, in combination with the wrong aperture or ISO, your picture will be completely white. This will also work vice versa, when a very high shutter speed in a low light situation is chosen, not corrected with ISO and aperture, your picture will result in a complete black picture.
However, all new DSLR’s will tell you if your shutter speed is over, or under, and thus are easily corrected for. Now, it is also a matter of what you are shooting, and in which situation, that will determine your choice of shutter speed. Lower shutter speeds, such as a couple of seconds are great for night photography, allowing more light to travel onto the sensor. But during the day a lower shutter speed will also come the shakiness of your own hands and thus making your pictures less sharp. However, would you want to capture a moving object, such as in sports you would want to stick to a higher shutter speed, you would have to correct other factors of exposure by changing the aperture and ISO. Here are some basic rules of shutter speed you would want to stick to:
- When shooting hand held you don’t want your shutter speed to go below 1/100s. Yes, this is one hundredth of a second. If choosing a shutter speed lower than 1/100s you might risk blurriness in your photo.
- The higher the shutter speed, such as 1/1000s, the sharper your moving object will be. You will want to use high shutter speed for sport photography or action shots.
- With low shutter speed, such as 1/5s or lower, you will want to use a tripod. This will allow you to lower your shutter speed even down to seconds so you could shoot the milky way, or the movement of the light of cars along a highway, without decreasing the sharpness of your picture.
Still not sure what do with shutter speed? Watch the following video!
And lastly, the third pillar that is a part of exposure, is ISO. ISO, simply put, is the sensitivity of your image sensor in your camera. A low ISO, such as ISO 100, means that the image sensor is less sensitive. If you increase the ISO, your image sensor will become more sensitive, allowing to pick up more “information”. However, increasing your ISO is not always the best idea. Increasing the ISO, and thus making the image sensor more sensitive, could mean that the camera picks up information it isn’t supposed to, in the photography world they often refer to this as noise. Besides that, increasing your ISO to too high will also reduce color accuracy and reduce it’s dynamic range.
To avoid this, you should always try to set your ISO as low as possible. However, ISO and the effects of increasing your ISO is different for every camera. The best thing you can do is try out different settings, and see how far you can up your ISO without loosing image quality. In general, you will use a low ISO in well lit situations, such as outdoor photography. While indoors, due to less light being present, you might need to up the ISO to get all the “information” you need on a picture. The best thing you can do is follow the following rules:
- Always try to decrease your ISO to set it as low as possible.
- For outdoors ISO 100 or 200 should almost always be good enough.
- When shooting non moving objects inside, for example, you can decrease your ISO by changing your aperture or shutter speed.
- For night photography, such as shooting the milky way, you will want to set your ISO higher since you want that extra “information”.
Still not sure which ISO settings to use, maybe this video will clear things up!
As you might have figured out by now, all three of these pillars that together form exposure, are connected. This means that changing one variable, will often result in a change of the other two variables. Depending on what your object of shooting is, and what your goal is, you might want to prioritize optimizing one of the three over the other two variables. Depending on what I am shooting, my reasoning goes as follows:
- For portraits, optimize aperture to create depth of field. A larger aperture, allowing more light in my camera, will also allow me to set a higher shutter speed and a lower ISO.
- For fast moving objects, I optimize for shutter speed to create a sharp image. Optimizing for a higher shutter speed, might mean I have to increase my ISO since less light will fall on my sensor, or that I have to choose a larger aperture.
- For outdoor photography my ISO is standard set to a 100, which is as low as I can set my ISO. I do not change the ISO unless I switch to indoor photography, for which I will often use a tripod to correct for using a lower shutter speed.
And the list could continue, I think by now you will get the connection and how to work with aperture, shutter speed and ISO. If you don’t, no worries! The best thing you can do is trial and error, use your camera and shoot the same picture with different settings and see how it affects the picture. Once you get a hang of it, you might even opt to shoot fully manual with your DSLR, allowing you to have maximize the abilities of your DSRL.
How about you, do you have any tips or tricks you would like to share with us? Or perhaps a question left unanswered? Tell me in the comment section below. Oh, and don’t forget to pin it!