It can be incredibly frustrating when you look at your photos and discover that they are blurry. Here are some of the most common reasons why

Beginner

Captured a stunning shot but found on closer inspection the image is blurry? You’re not alone. All image-makers will encounter blurry images at some point in their photography journey. But by being aware of what causes blur and how to prevent it–you will go a long way to ensuring your images are sharp.

Camera shake


One of the biggest culprits for blurry photos is when the camera moves when the shutter is open. This is known as camera shake. The leading cause of this is selecting a shutter speed that is too slow for you to handhold a camera. Generally, the slowest speed to handhold a camera is 1/60 sec. Although improvements in image stabilisation technology (technology either inside a lens or camera that helps reduce camera shake) have meant some people can select slightly slower shutter speeds and still capture sharp photos when handholding. But to be sure that your images will be sharp at slow shutter speeds (anything slower than 1/60 sec), you need to use a tripod.

I took this photo at 1/10th second shutter speed–which is far too slow for handheld photography and resulted in blur from camera shake
1/40th second shutter speed was too slow to freeze the action and capture a sharp photo in this scenario

Tripod issues


But simply using a tripod does not guarantee you sharp photos. There are several key considerations and adjustments you need to make to your camera when using a tripod:

Be aware of vibrations on railings and bridges when using a tripod. They can easily cause your tripod to move when taking a photo–which will result in blur

Even with a tripod this photo is not completely sharp as the image stabilization was not turned off
For long exposures, you need to ensure you lock up your mirror. This photo was taken with a 20-second exposure using a tripod. But there is noticeable blurriness
This is what might happen if you press the shutter release button on a long exposure (13 secs) shot

Moving subject


It is much harder to capture a sharp image of a moving subject. Unfortunately, there is no universal setting that can help. My advice is to always go faster with your shutter speed than you think you might need. For example, photographing a moving person might require a shutter speed of 1/200 sec to freeze the action. But photographing a moving vehicle might need to be as fast as 1/2000 sec.

The photo on the left is blurred, however with better focusing and a faster shutter speed the photo on the right is much sharper

Focus


The other tricky element of photographing moving subjects is making sure you are focusing correctly. For example, if someone is running toward you, your focus point will be continuously changing. If you focused on where they started, they would be blurred by the time they are closer to you. In these instances, you need to ensure you have selected “continuous focus” in your camera setting so that the camera continues to track the subject and focuses on it for as long as you hold the shutter button down halfway.

It is also essential to make sure you are focusing on the correct part of the image. Say you are taking a portrait of someone with a wide aperture (a low f/stop number) this will mean a shallow depth of field. If you then mistakenly focus on the an area other than the subjects face, it will be blurred.

The focus in this image is slightly wrong. Here, the eyes shout to be sharp, but the focus is on the mask instead

Aperture


Another issue regarding focusing is your depth of field (the distance in your photo where things will be sharp). Selecting the wrong aperture for the type of photo can mean that your image is out of focus. This is important in landscape photography or cityscapes, where you need the whole scene to be sharp. For any type of photography that requires a greater depth of field, you should set your aperture to f/8 or smaller.

But also remember to be careful about your focus point when using a shallower depth of field, as even a tiny error in your focus point will mean your main subject might be out of focus.

This shot should be taken with a small aperture for maximum depth of field (Something like f14-f16) to get a sharp cityscape. Taking this photo at f/4.5 has meant there are parts of the scene that are soft

Diffraction


As mentioned above, you will need a greater depth of field for some genres, such as landscape photography. However, it is essential to know that when you select extremely small apertures of f/18 or smaller, it can have a detrimental effect on your photo’s sharpness. This is known as diffraction.

Without getting too technical, diffraction is caused by the lens’s optics and how light waves become more separated when entering the lens at smaller apertures. They then clash with each other and can cause the image to look soft. So, keep your aperture to no more than f/16, and if you want to use a smaller aperture, make sure you test the results before using it in the field.

This photo was taken with an aperture of f/29–you can see how blurry the photo has become because of diffraction

Noise


Every photo will have noise (grain and pixel elements) in it. But most of the time, in good light, the noise will be almost invisible and won’t be noticed. However, in extreme cases, noise in an image can cause it to look significantly worse. The result will be a grainy looking shot that seems blurred.

The most common cause of excessive noise in an image is by selecting a high ISO. The higher your ISO is in your exposure settings, the more noise will appear in your image. So, as a rule, always choose the lowest ISO that you can when taking a photo. Learn how to use ISO effectively with our dedicated guide here.

The photo above was taken at ISO 6400. There is excessive noise in the image which makes the overall appearance look soft

Unclean lens


It might seem like an obvious point, but make sure your lens glass is clean and smudge-free. Get into the habit of regularly wiping your lens with a microfibre cloth when you’re out in the field.

Smudges on the lens (left) can cause significant blur and a soft looking scene–as seen with the comparison above. Photos by Philip Mowbray

Blurry photos can be incredibly disheartening. But by following the tips above–you will be able to eliminate many of the common causes of blurred images.

All images by Kav Dadfar unless otherwise states.