Nov 10, 2014

[Photography] Top 10 Mistakes that Cause Blurry Photos

Cedar Key


If your photos are not sharp, you are not alone! The most common question I get asked by beginning photographers is “how do you get your images so sharp?”


Blurry photos is very common issue with a whole plethora of possible culprits, making it very difficult to pinpoint exactly what the problem is. But if you go through this list of the top 10 mistakes that cause blurry photos, you will probably find the answer that works for you.


1. Your shutter speed is too slow


This is the #1 culprit of blurry photos. You might think you can hold perfectly still for half a second, but I assure you there are very few people in the world who can. When hand-holding your camera, remember this rule of thumb to avoid blur caused by camera shake – your shutter speed should be the reciprocal of your lens’ focal length – that is, if you’re using a 60mm lens, your exposure should be 1/60th of a second or faster. With a 200mm lens, use at least 1/200th of a second, and so on. Camera shake is magnified the longer your telephoto length, so wider angle lenses will suffer its effects much less.


Using a 400mm lens, I selected a shutter speed of 1/400th of a second to reduce the possibility of camera shake.

Using a 400mm lens, I selected a shutter speed of 1/400th of a second to reduce the possibility of camera shake.



Some lenses and cameras have image stabilization technology built into them – particularly with longer focal lengths. Image stabilization usually allows you to slow your minimum shutter speed by around three stops, meaning that a 60mm lens can now handle shutter speeds as low as 1/8th of a second without camera shake.


What is YOUR minimum shutter speed?


In addition to this rule of thumb, it’s important to know your own personal minimum shutter speed. We all shake a little, some more than others, so it’s good to know at what point camera shake becomes an issue for you. Try an exercise to find out: put your camera in shutter priority mode and make the same photo at 1/500th of a second and keep going slower and slower. Back at your computer, look at your images and see when you start to notice the blur. Personally, I don’t usually go below 1/125th of a second if I’m hand-holding my camera.


2. Not using a tripod


Sunset Arches


If you’re experiencing camera shake and you can’t use a faster shutter speed (due to low light conditions) or you don’t want to use a fast shutter speed (because you’re purposefully trying to blur something in the frame) then you need to steady your camera another way such as using a tripod or monopod.


When you use a tripod, image stabilization is not necessary and may even be counter productive, so it’s a good idea to get in the habit of turning it off when you put your camera on a tripod and turning it back on when you take it off.


3. Bad camera holding technique


For the best stability, practice the official photographer position: stand with your feet slightly apart, one staggered forward, and firmly planted to stabilize your body right-to-left and back-to-front. Support the camera with your left hand by holding the lens from underneath, and use your right hand to grab the grip and gently press the shutter button. Tuck your elbows tight to your chest and use the viewfinder rather than the live view screen, as holding the camera to your face will also help hold it steady. Some photographers even go so far as to listen to their breathing and heartbeat, taking care to fire the shot in between breaths and beats for maximum stability.


Proper technique when hand-holding your camera.

Proper technique when hand-holding your camera.



4. Your aperture is too wide


The size of the aperture also has a direct effect on the sharpness of your photo in that it determines depth of field, which is how much of the image is in focus from front to back.


When a lens finds focus, it locks in on a specific distance known as the plane of focus. If your focus is at, say, 15 feet, everything 15 feet away from the camera will have maximum sharpness, and anything in front of or behind it will start to fall into blur. The amount of this effect depends on the aperture.


If you use a wide aperture, like f/2.8, the depth of field is very shallow. This effect is emphasized with longer focal length lenses. So if you are using a telephoto lens and the aperture is f/2.8, there may be only a razor thin sliver of the image that is in sharp focus. If you use a small aperture, like f/11 or f/18, the depth of field is larger so more of the image will be sharp.


Choosing the right aperture depends on the type of image you want to create. But if you are trying to get everything in the frame as sharp as possible, try using a small aperture (a larger f-number such as f/11 or f/22). However, by using a small aperture you will need to use a slower shutter speed to compensate for the loss of light. See problem #1.


5. Not using autofocus


How good is your eyesight? Not great? Wearing glasses? You should probably be using autofocus. These days cameras are sophisticated – let them do what they are good at. Another thing to keep in mind is that your viewfinder should have a diopter on it. It’s a little wheel next to your viewfinder that allows you to adjust how clearly things appear when you look through it. It is particularly useful for people who should be wearing glasses but are not.


Black Vulture in Flight


6. Not focusing in the correct place


Even if you have a sharp, clear prime lens on a bright day, using a small aperture and a fast shutter speed with a low ISO, it doesn’t count for much unless you can get the camera to focus on the right spot. This is even more crucial when using a wide aperture, which can create a razor thin depth of field. A slight miscalculation in the focus can throw the subject completely out of the focal plane, or give you a portrait with a perfectly sharp earlobe and blurry eyes.


Often photographers leave their cameras set on auto-area AF mode, which tells the camera to use its best judgment to decide what part of the picture should be in focus. Most of the time modern cameras are pretty good at this, particularly if the subject is prominent in the frame. However, with more complex compositions the camera can get confused and try to focus on the wrong thing. To specify the focal point yourself, switch to single-point AF area mode.


f-spotWhen you look through your viewfinder, you should see an array of little dots or squares laid over the display. These are your focus points, and they show you where in the frame the camera is capable of finding focus. In single-point AF area mode, you can use the camera’s direction pad to select one of these dots, and the camera will always focus on that point and that point alone.


To tell the camera to focus, you would normally depress the shutter button halfway before pressing it the rest of the way to take the shot. This works pretty well, but can be sensitive – if you press too lightly, it may come unpressed and try to re-focus after you’ve already found your spot. If you press too hard, you might make the exposure before the focus is ready. If you take multiple pictures in succession, it will try to focus again before each shot. For these reasons, some photographers swear by the back focus button instead.


This is a button on the back of your camera, probably near your thumb. It might be labeled “AF-On” or simply “Fn”, and it might be set up by default or you might have to activate it in your camera’s menu settings, but it can be assigned to take over the autofocus function. When you press it, the camera focuses and won’t focus again until you press the button again. This way, you can re-compose and take shot after shot, and the camera won’t lose your focus every time you hit the shutter button.


7. Using the incorrect focus mode


There are three main autofocus modes that every camera should have. The first is single-shot focus, usually called AF-S or One-shot AF; it is meant to be used with still subjects. The second, continuous autofocus (AF-C or AI Servo) is specially designed to track movement through the frame, so is best to use when your subject is in motion. The third is an automatic mode, AF-A or AI Focus AF, and likely the default setting on your camera. It reads the scene and determines which of the first two modes it should use.


Cactus Flower


8. Not using manual focus


While I’m a big advocate of autofocus, there is one particular time when manual focus comes in very handy. When your camera is on a tripod and you are using a wide aperture to achieve a very shallow depth of field, and you want to make sure the most important thing in your frame is sharp, switch to manual focus and then use the LCD zoom function to magnify the display by 5x or 10x allowing you to make tiny adjustments to the focus to get it just right.


9. Junk on or in front of your lens


If you have a big smear on your lens, that is going to affect the clarity of your image. By the same token, if you put a cheap plastic filter in front of your lens, that is going to degrade image quality as well. If you always use a UV filter, you might want to try taking a few shots without it to see if the quality of your UV filter is negatively affecting your images.


Using an aperture of f/20, everything is sharp from foreground to background.

Using an aperture of f/20, everything is sharp from foreground to background.



10. Poor lens quality


This item is last on the list for good reason; it is the most common thing for beginners to blame their blurry images on, but it is rarely the real reason. Still, lens quality does make a difference.


Lens quality is determined by the materials and construction inside the lens itself, which is usually made up of several pieces of glass precisely aligned in order to focus, zoom, and correct for optical aberrations.


Some lenses are simply sharper than others or are better in different ways. Some lenses may be sharp in the center, but get blurry around the corners and edges of the image. Some are clear at certain apertures but slightly fuzzy at others. Some lenses cause colour fringing around points of contrast. Every lens has a unique character that may or may not be useful to the type of work you’re doing. It’s also worth noting that each lens has a “sweet spot” – a certain aperture at which it performs its best. This is usually in the middle of its aperture range, around f/8 or f/11.


For the sharpest image quality, fixed focal length lenses usually take the cake. It’s not always convenient to carry around two or three lenses rather than a single all-purpose zoom, but their simple construction makes even the cheapest prime lens crystal clear.


The post Top 10 Mistakes that Cause Blurry Photos by Anne McKinnell appeared first on Digital Photography School.







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