How to stick your smartphone photos every time with this exposure guide for beginners

Have you ever taken a picture with your smartphone only to realize later that it was either too dark or too light? It’s frustrating, isn’t it?

The secret to perfect light balance in photographs lies in exposure. Although it sounds technical, once you understand how it works, you’ll be able to take control of your smartphone camera and instantly improve your shots.

What is exposure and why does it matter?

Exposure refers to how much light your camera lets in when you take a photo. Too much light (overexposure) and your image will look washed out and too bright. Too little light (underexposure) and your photo will be dark and lacking in detail. Getting the exposure right means capturing the right amount of light so your images look natural and balanced.

Smartphones usually have automatic exposure settings that do a decent job most of the time. But if you want to step up your photography game, learning how to manually adjust exposure can make a huge difference. And this is where understanding the exposure triangle comes in.

Understanding the exposure triangle

The exposure triangle is a simple way to understand how three key settings—ISO, shutter speed, and aperture—work together to control the light in your photos. Think of it as a balance between these three elements. When you change one, you may need to adjust the others to keep your photo well exposed.

Here’s how each part of the exposure triangle affects your photography…

ISO

ISO indicates how sensitive the camera’s sensor is to light. A low ISO setting means your camera is less sensitive to light, which is great for bright conditions, such as when you’re outside on a sunny day. The high ISO sensitivity makes the camera more sensitive to light, which is useful in low-light situations such as an evening event or a dimly lit room.

However, there is a trade-off: when you increase the ISO, you may experience more “noise” or grain in your photos. This can make them look less sharp or bright. So while increasing the ISO can help you take photos in low light, it’s best to keep it as low as possible to get brighter, sharper images.

Below is a comparison of photos taken at the same location at different ISO levels:

Shutter speed

Shutter speed determines how long the camera’s sensor is exposed to light. A faster shutter speed means the sensor is exposed for a shorter time, which is great for freezing fast-moving subjects, like when you’re shooting a sporting event or your pet running around.

A slower shutter speed allows the sensor to capture light for a longer period of time, which can help capture more detail in low-light situations or create great motion blur effects.

Simply put: fast shutter speeds freeze motion, while slow shutter speeds capture motion over time. Take a look at the example below – on the left you can see a photo taken at a high shutter speed that freezes the action, while on the right a slower shutter speed captures motion blur.

If you’re trying to take a picture of something moving fast—like a car or a bird—you’ll want to use a faster shutter speed to avoid blur. On the other hand, if you’re shooting something still in low light, a slower shutter speed can help brighten the photo.

Opening

Aperture refers to how wide the lens opens when you take a photo, which determines how much light comes into the camera. Think of it like the pupil in your eye – when it’s wide open, more light gets in, and when it narrows, less light gets in.

In photography, aperture is measured in “f-stops”. A lower f-stop number (like f/1.8) means a wider aperture that lets in more light and creates a shallow depth of field. This shallow depth of field is what gives you that beautiful blurred background (bokeh) effect, where your subject is sharp but the background is soft.

A higher f-number (like f/11) means a narrower aperture that lets in less light but keeps more of the scene in focus, making it ideal for landscape shots.

Most smartphones do not allow manual aperture settings like traditional cameras. However, modern smartphones often have “fixed aperture” lenses that work to simulate aperture effects. Portrait modes, for example, use software to mimic the shallow depth-of-field effect you’d get with a wide aperture on a traditional camera.

Below is an illustration of how aperture affects your images (note the background blur in the first image):

How to adjust exposure on your smartphone

Once you understand the exposure triangle, you can start taking control of your smartphone photography. Here are three effective ways to adjust exposure, listed in order of ease of use:

Use the exposure slider

Most smartphone camera apps include an exposure slider, usually represented by a sun icon. Once you’ve framed your shot, tap the screen where you want to focus and a slider will often appear. Drag up to lighten the photo, drag down to darken it.

This method is the easiest way to adjust exposure on the fly, ideal for quick fixes without diving into complex settings.

Shoot in Pro mode

If your smartphone has a “Pro” (or “Manual”) mode, this gives you more control over your camera settings. In this mode, you can manually adjust ISO, shutter speed, and exposure balance. While this requires a bit more understanding of how these elements interact, it allows for precise adjustments based on your shooting conditions.

Unfortunately, iPhones don’t have a manual mode, but this is how it looks on a Samsung Galaxy:

Use a third-party camera app

If you want even more flexibility than your phone’s default camera app offers, consider downloading a third-party camera app like Focos or ReLens. These apps typically provide advanced features, including separate controls for ISO, shutter speed, and exposure compensation. Although there is a slight learning curve, they offer powerful tools to help you fine-tune your photos to your liking.

Mastering exposure is key to taking stunning smartphone photos that truly capture the moment. Understanding the exposure triangle—ISO, shutter speed, and aperture—gives you the tools you need to adjust how light affects your images. Whether you’re shooting in bright sunlight or low light, the right exposure can elevate your photos from ordinary to extraordinary.