There are three main camera settings to consider when taking a photo: ISO, aperture and shutter speed. This blog post touches on what each of these mean and how to set them.
ISO/ASA
The ISO of a film tells you how light sensitive it is. It also determines how grainy the images will be.
- ISO 100 = less light sensitive, less grainy, good for bright sunny days outside
- ISO 400 = more light sensitive, slight grain, good for overcast days outside and indoor scenes
- ISO 800 = very light sensitive, grainy, good for night time
Setting your ISO on a film camera is easy because you typically want to set it to the same speed as the film you are putting in your camera. There is usually a number associated with each type of film labeled on the box. This is the ISO you want to set on your camera.
Here are some examples:
- Ilford HP5 400 = ISO set to 400
- Kodak Portra 800 = ISO set to 800
- Fuji CN200 = ISO set to 200
The ISO numbers listed in the diagram are always fixed
The ISO dial on your camera is typically on the top of your camera to the lefthand side underneath the rewind knob. It will be the dial with numbers ranging from 50 to 3200 and is typically marked ASA.
Closeup of ASA dial on Nikon FE camera
Aperture
A camera's aperture determines an image's depth of field. It allows you to make the background either in focus or blurry to highlight a subject. Aperture is measured by F-Stops ranging from 1.4 - 22. The F-stops listed in the diagram below are always fixed.
Low Apertures
When the aperture is set to a lower number (f1.4 - f8), the shallower depth of field means the closest subject to the lens will be sharp but the background will be blurry. When the aperture is set this low the lens dilates allowing more light to come into the camera.
High Apertures
When the aperture is set to a bigger number (f11 - f32), the deeper depth of field means all subjects will be in focus even in the background. When the aperture is set this high the lens contracts allowing less light to come into the camera.
The aperture dial will be located on your lens. This is a setting that is typically not on the camera body. The dial will be at the base of the lens closest to the camera and will have numbers ranging from 1.4-32. Depending on the camera you may be able to see the aperture you camera is set to when you look through the view finder.
Closeup of aperture f-stop settings on camera lens
Shutter Speed
A camera's shutter speed determines how sharp or blurry your image will be. It is measured in seconds and can range from 1/1000 of a second to 5 whole seconds. Typically the numbers in the diagram represent the most common speeds you will see on your camera with maybe some faster and slower speeds.
Tip: Shutter speed dials on cameras usually do not list the speed in fraction form, so remember that if you set your shutter speed to a bigger number such as 250 it is actually a very small fraction of a second.
Fast Shutter Speed
When the shutter speed is set to a bigger number (1/1000 - 1/60) any movement will be stopped and in focus. The shutter will open and close much faster preventing a lot of light coming into the camera.
Slow Shutter Speed
When the shutter speed is set to a smaller number (1/30 - ½) any movement will be visible and make the image appear blurry. The shutter will be open for a longer amount of time allowing more light into the camera.
The shutter speed dial is typically located on the top of your camera on the right hand side. It will have numbers ranging from 1-1000.
Closeup of shutter speed dial on Nikon FE camera
The Exposure Triangle
Each setting, ISO, aperture and shutter speed, is necessary to understand when wanting to shoot an evenly exposed image. When you set one of these settings it has an affect on the other settings as well because each setting changes how much light is coming into the camera.
So let's say you want to set your camera to a faster shutter speed since you want it to be as sharp as possible. This means that not much light will be coming into the camera. Depending on the light conditions, you may need to set your aperture to a smaller number to make the lens dilate and balance the lack of light due to the fast shutter speed.
The exposure triangle can be a helpful diagram to look at to understand the relationship between each of these settings better.
There is a lot to remember with each of these settings and when you are out photographing it is hard to know what you should set your camera to based on the light conditions. This is where the Sunny 16 Rule can help or even having a light meter to help measure the light conditions so you know how to exactly set your camera to get an even exposure.
Luckily we have created a blog post describing the Sunny 16 Rule. We also have a blog post about how to use light meters. Check these out to get a better sense of how these settings are used when out taking pictures.