Understanding Essential Camera Settings
Why shoot manual?
Shooting in manual mode allows you to completely control the capture settings. In long exposure photography, this control is essential in order to achieve the intended result. In this video, Paul covers why this control is so important.
If you've never shot manual before, or are unsure why it makes a difference, watch this video before we dive into each of the capture settings and how they work together.
How long is your camera collecting light?
What is shutter speed?
The shutter speed indicates how long your sensor is collecting light. A fast shutter speed will freeze action, but let in less light, whereas a long shutter speed will result in blurred moving objects, but let in much more light. By adjusting the shutter speed, you can brighten or darken the captured image. A fast shutter speed will ensure a well-exposed image on a bright, sunny day. A slow shutter speed on that same bright, sunny day would result in an overexposed image.
Shutter speed is written as a fraction of a second – for example, 1/125 is 0.008 of a second.
Paul goes into more detail on shutter speed in the accompanying video.
What is the amount of light being collected?
What is aperture?
Aperture indicates how large the opening allowing light in is - or the amount of light that will be collected. Aperture also controls depth of field in your image. A smaller opening – a larger aperture value – will let in less light and create a deep depth of field. A larger opening – a smaller aperture value – will let in more light and have less of the image in focus - a shallow depth of field. For landscape photography, you will generally want a deep depth of field, and therefore larger aperture values.
Aperture values are shown as f/X.X – for example, you may have a prime lens with an aperture of f/2.8. Or you may have a lens with a range of aperture values – for example, f/2.8-5.6. The upper value in that range is 2 f-stops darker. Light has decreased by half if the value has increased by one f-stop, or light has doubled if the value has decreased by one f-stop.
How sensitive is your camera to light?
What is ISO?
The ISO value indicates how sensitive to light your camera’s sensor is allowed to be. A low value is less light sensitive, whereas a large value is more light sensitive. This means that by increasing ISO, you are able to brighten your image. This is useful if you would need a longer shutter speed at a low ISO to get a well-exposed image, but you have a moving element in the scene that you would like to freeze in action. You can then increase the ISO and decrease your shutter speed. However, increasing ISO introduces noise into your image. So, for most long exposure photography, you will want to keep your ISO as low as possible to reduce the amount of noise recorded in your image.
Putting it all together
How do I put it all together for a perfect exposure?
Shutter speed, Aperture and ISO all work together to create a well-exposed image. You can think of them as a triangle that you need to keep in balance. If you adjust one to get a certain effect, then you must adjust the others to compensate for the change. We just talked about keeping ISO as low as possible for most landscape photography, so that leaves you with two options to increase the amount of light that reaches your sensor. In long exposure photography, you will generally use a combination of both aperture and shutter speed, as well as filters (which extend your shutter speed by letting in less light), to achieve the type of effect you are aiming for.