Camera settings explained: ISO, shutter speed & aperture

Shutter speed is one of the three main camera settings that determine the exposure of your photograph, along with aperture and ISO. It refers to the amount of time the camera's shutter stays open to allow light to reach the image sensor or film. You may see this as a fractional number, like 1/200, which literally means fractions of a second. The higher the denominator, the faster your shutter speed will be.

The shutter speed controls two things in your images: motion blur and exposure. A faster shutter speed allows less time for light to hit the sensor, resulting in a darker exposure but freezing any movement in the scene. Conversely, a slower shutter speed lets in more light for a brighter exposure but increases the chances of capturing motion blur. If you’re familiar with nightlife photography or those images of roads with cars and lots of lights following them - those are taken with a slow shutter!

For example, a shutter speed of 1/1000th of a second can freeze fast action like a hummingbird's wings or a race car zipping by. On the other hand, a slow shutter speed of 1 second or longer will blur any movement in the frame, which can create artistic effects like silky waterfalls or the aforementioned light trails from passing cars. The latter is usually taken on a steady surface or a tripod to ensure the rest of the image remains in focus.

Aperture refers to the opening inside the lens that allows light to travel through and reach the camera's sensor (or film). Think of it like the pupil of the human eye, which controls how much light enters. A larger aperture opening (smaller f-number like f/1.2) allows more light to pass through, while a smaller aperture (larger f-number like f/11) restricts the amount of light.

With a larger aperture, more light hits the sensor, resulting in a brighter exposure. This is ideal for low-light situations or when you want to use a faster shutter speed to freeze motion. Conversely, a smaller aperture lets in less light, which is useful for achieving a longer depth of field or when you need to use a slower shutter speed, such as in bright outdoor conditions.

So surely you want as much light as possible, right? The answer is generally yes, but the aperture also plays another crucial role - depth of field.

Depth of field refers to the zone of “sharpness” in an image, extending from the nearest point of focus to the furthest point. A large aperture (small f-number) produces a shallow depth of field, which can beautifully blur the background while keeping the subject sharp. This effect is often used in portraiture to draw attention to the subject or produce bokeh effects. However, a small aperture (large f-number) increases the depth of field, keeping both the foreground and background in focus, which is desirable for landscape photography or when you want to capture sharp details throughout an entire composition.

Mastering the aperture of your camera can seriously improve the clarity of your images, which is super important for photo printing and generally having nice photos to marvel at! Here are some quick tips to master aperture:

1. Open your aperture for more light

If you’re in a dark place or shooting at night time, you’ll want to keep your aperture as wide as your camera or smartphone will allow you to. 

2. Close your aperture for sharpness

A wide aperture is great for portraits as it can keep tiny details in focus whilst blurring a background. But if you’re shooting landscapes or group photos where you want everything in focus from foreground to background, use a narrower aperture. This increases the depth of field, keeping more of the scene in acceptable focus.

ISO refers to the light sensitivity of the camera's sensor or film. High ISO values make the sensor more sensitive and able to capture images in low-light conditions, whereas low ISO values allow you to shoot in super-bright conditions.

In the days of film photography, ISO referred to the specific film's light sensitivity. With digital cameras, ISO relates to the sensor's ability to gather light. A higher ISO setting allows the sensor to capture more light, enabling faster shutter speeds or smaller apertures in low-light situations.

Photographers often need to balance ISO with shutter speed and aperture to achieve the desired exposure and image quality. Higher ISOs allow for faster shutter speeds to freeze motion or smaller apertures for increased depth of field but at the cost of increased noise and potential loss of detail.

Noise

Having too high of an ISO value also introduces more digital noise or grain to the image. This noise appears as unwanted discoloured pixels or specks, degrading the overall image quality. Lower ISO settings, like 100 or 200, produce cleaner images with less noise but require more light or longer exposures. With the introduction of AI, apps such as Lightroom and Photoshop now have a “Denoise” feature, which allows photographers to remove noise whilst retaining the clarity of their images.

So why should you care about noise if you can just remove it? Because it doesn’t retain the images’ true clarity!

1. Keep your ISO as low as reasonably possible

As a general rule, try to use the lowest ISO possible to minimise noise. For well-lit outdoor scenes on a sunny day, stick to ISO 50-400. When shooting indoors or in shaded areas, bump up to ISO 800-1600. Only go above ISO 1600 if you need to in very low light and don't mind some graininess. Most modern cameras handle noise quite well up to around ISO 3200!

2. Bump up your ISO for fast shutter speeds

If you are shooting handheld, use a higher ISO like 800-1600 to allow for a faster shutter speed and prevent blurry shots from camera shake. For tripod shots where a slow shutter isn't an issue, use a lower ISO in the 100-400 range.

3. Utilise auto ISO if necessary

Many cameras also have an "Auto ISO" mode that automatically adjusts the ISO based on the lighting conditions. This can be convenient for run-and-gun shooting, but you lose some control. It's better to get comfortable picking the ISO manually for more consistent results. It’s a great way to experiment with how your camera adjusts to different lighting conditions though, and can help ease the transition from auto to manual shooting!

4. Save your files in RAW format

Most smartphones now have the option for RAW image shooting. RAW files contain more data than JPEGs, giving you more flexibility to reduce noise during post-processing on your computer or smartphone editing app. You can't eliminate noise entirely, but shooting RAW gives you the best chance to do so, as it means your original image won’t be compressed (which JPEGs usually are).

The exposure triangle is an important concept in photography that highlights the interplay between shutter speed, aperture, and ISO. These three elements work together to regulate the light that hits the camera sensor or film, which in turn influences the exposure of your photograph. Grasping how these settings interact is essential for obtaining the right exposure and achieving the results you want!

Aperture

A lower f-stop value means a bigger hole letting more light into the camera. This creates a narrow area in focus, which can blur the background (or foreground). A higher f-stop shrinks the hole, cutting down the light that gets into the camera, and widening the area in focus so more of the scene looks sharp.

Shutter speed

Shutter speed tells you how long the camera's shutter stays open allowing light to hit the sensor. We measure it in seconds or parts of a second, and it decides how much movement or motion blur shows up in the picture. A quicker shutter speed stops motion and cuts down on blur making it great to capture something moving, like an athlete or a bird flying by.

ISO

ISO is all about how sensitive a camera is to light. It determines the amount of light needed for a well-exposed shot. When you use a low ISO setting, your camera doesn't pick up as much light, but you end up with cleaner images that have less noise or grain. On the flip side, cranking up the ISO makes your camera more light-sensitive, but you'll notice more noise or grain in your pictures.

To achieve proper exposure, you need to balance these three settings simultaneously. For example, in low-light conditions, you might need to increase the ISO to compensate for a faster shutter speed (to avoid motion blur) or a smaller aperture (for greater depth of field). In bright sunlight, you might use a lower ISO, faster shutter speed, and smaller aperture to avoid overexposure.

If you own a DSLR and you’re still getting to grips with it, you have noticed a dial with letters and symbols. If you have no idea what they mean - we’ll explain some of them to you in the context of aperture (Av), Shutter (S or Tv) and Program (P) modes.

Aperture mode - Av

In aperture priority mode on a DSLR, you can set the desired aperture value, and the camera sets the shutter speed to ensure correct exposure. This mode helps when the photographer wants to control the depth of field, like creating a blurry background effect with a wide aperture or keeping a sharp focus throughout the scene with a narrow aperture.

Shutter mode - Tv or S 

In shutter priority mode, you can pick the shutter speed, and the camera sets the aperture to achieve proper exposure. This mode works well for situations where controlling motion blur or freezing action matters such as capturing a moving subject with a fast shutter speed or creating a sense of motion with a slower shutter speed.

Program or ISO mode - P

When using ISO priority mode, you pick the ISO setting you want, and your camera figures out the right aperture and shutter speed to get the exposure right. This setting comes in handy when you need to control how sensitive your camera is to light. It's useful when the lighting keeps changing, but you don't want to mess with the depth of field or how much motion blur you get.

If you plan to print photos from your smartphone, then mastering the exposure triangle will ensure your photos are print-ready! 

Smartphone cameras have come a long way in recent years. In fact, many modern smartphones offer manual controls for adjusting settings like shutter speed, ISO, and even aperture.

One key difference is that smartphone cameras mostly have a fixed aperture, meaning you can't physically adjust the size of the opening. Instead, they simulate different aperture values through computational photography techniques. This can limit the depth of field effects you can achieve compared to larger camera sensors.

Shutter speed and ISO controls work similarly on smartphones as they do on cameras. Slower shutter speeds allow more light in but increase the risk of blur from camera shake or subject movement. Higher ISO settings amplify the sensor's light sensitivity but can introduce more noise or grain.

Many smartphone camera apps provide pro/manual modes that let you independently control shutter speed, ISO, white balance, and sometimes aperture simulation. Using these can help you achieve specific looks or expose scenes more accurately than auto mode.

Here are some quick tips for getting great results from your smartphone camera:

• Use a tripod or stable surface for low-light shots with slow shutter speeds
• Tap on your subject via the phone’s screen to refocus
• Adjust exposure compensation to brighten or darken the overall image
• Explore add-on lenses for wider angles, macro, etc.
• If you’re able to, shoot in RAW format if supported for greater editing flexibility
• Use your volume buttons or headphone remote as a shutter release
• Use grid overlays to improve composition

We hope this guide has helped you understand the exposure triangle in greater detail! For more photography tips and gift inspiration - head on over to the Max Spielmann blog. Locate one of our stores for more information on photography and same-day photo printing from our friendly colleagues!