The blur police came to me many times and I’m sure they pulled you over before too. That moment when you take that stunning photo, just to realize at a closer look... That it's blurry!! Well, not to worry, here is my complete guide on how to capture super sharp pictures from now on!
Why Did This Happen To Me?
Well to say it simply: it usually is related to focusing, shutter speeds, physical movements, and a variety of other factors. This of course doesn't say much, so keep on reading to learn more!
Now focusing is what you're most familiar with, but perhaps the most complicated part on this list. Before taking any photograph, you have a variety of settings to choose from, starting with either manual or auto. Most likely you aren't going to use manual as it isn't practical to use with most subjects, and modern autofocus technology is pretty reliable.
options for autofocus methods
- AF-(Single)-Servo: this will allow the camera to stop focusing once it confirms that the subject is in focus. Note that usually, the camera will not allow you to take any pictures until it locks the focus. This option is not recommended unless you are taking pictures of still life or landscapes.
- AF-Continuous: as long as you are holding down the focusing button, the camera will be constantly refocusing. When you hit the shutter button, the camera will capture the picture no matter what. This option is most practical to use with portrait or wildlife photography.
- AF-Auto: you are letting the camera choose one of the above options.
Options for Focus Areas
- Single: this option lets you choose the exact point you want the camera to focus within the viewfinder. This is my preferred option as it gives the most control.
- Dynamic Area: you still select a specific point just like single, except if the subject moves away, the camera will adjust within the area of a specific amount of chosen points (e.g. 9, 21, 51).
- 3D Tracking: similar to single, except once you activate the focus, the camera tracks the motion of the subject.
- Auto: this uses algorithms to identify special features such as faces to focus on them.
Additionally, if you go through your camera's settings, you may find an option to turn on the thumb or back button focusing, which extremely helps with efficiency and to pay closer attention to details.
Now, what if your autofocus is perfect, but only part of your image is in focus? The mechanism that is responsible for that is known to be the aperture or iris of the lens. This controls the opening size within the lens which restricts light and detail sensitivity as it reaches the sensor. An important term associated with this concept (that you may already be familiar with), is called depth of field (DOF). Here is a demonstration:
- Shallow DOF - big opening (e.g. f2.8) = more light, but less detail sensitive
- Deep DOF - small opening (e.g. f22) = less light, but more detail
A good way to remember this is to use a painting analogy. Say we have a big paintbrush and a small paintbrush. The brushes will represent the aperture, the paint will represent light, and the canvas will be the camera sensor. If we use a small paint brush (e.g. f2.8), we can add more detail, but with less paint at a time. However, if we use a big paintbrush (e.g. f22), the opposite is true. A big brush will add more paint, but there will be less detail.
Now it is really important that you understand that you may not always want more detail or more light. For example, as portrait photographers, we only want the person in focus (>f2.8) as we don't need to be distracted by irrelevant details. Separating the subject from the background is a very quick way to capture a professional-looking portrait. However, if we were capturing a landscape, we would want everything in focus (<f22) as all visual elements will be relevant to us.
Now maybe poor focusing or aperture isn't the problem? Then I recommend you check out how motion blur caused by shutter speeds can ruin your photos. There are two factors that determine the appropriate shutter speed.
At a minimum, make sure your shutter speed is equal to the reciprocal of the focal length. For example, if you are using a nifty-fifty lens (50mm), then your shutter speed should be at least 1/50 of a second or faster.
The above statement only factors in focal length, but it doesn't factor in your movement of you in relation to your subject. If for example, you're taking pictures of someone running, then you're going to need a lot faster shutter speed compared to taking a picture of someone walking. Or perhaps they are walking, but you're in the back of a truck moving 30mph. Either way, you still are going to need a faster shutter speed. However, in my experience, I have found that it is possible to use a slower shutter speed for a fast-moving object if you are able to match the move with the subject. I personally think the best way to learn this, is through experience and experimentation.
Using a Tripod
A good way to help avoid motion-blur, you could just use a tripod or monopod, however, that isn't always practical. When not using a tripod, try to keep your elbows in, hold up your camera close to your body, breath-in, and take three pictures of your subject. This helps to stabilize your camera and get crystal-clear images. Sometimes camera sensors or lenses have stabilization or vibration reduction features that also help avoid motion blur.
You would think that ISO (the sensitivity and speed of the sensor to light) has nothing to do with getting sharp photos. Well, I changed my mind one night when I brought it up too high. Simply, the higher the ISO is equal to more noise, and the higher the noise is equal to color inaccuracy, a decrease in detail, and the creation of annoying artifacts. When you edit the photo later to get rid of the ugly noise effects, you will process some noise reduction, but it will make it look blurry. If possible, always try to keep your ISO near your camera's native range or below 800 (preferably 500).
Depending on the quality of the lens you may use, it can affect the sharpness of your image. Design, lens coatings, glass types, and technologies such as VR/IS all contribute to a sharp image.
Some of the lenses that I own for example have a fluorite coating on the glass with a precise autofocus mechanism, which will capture the most insane detail! It helps to have good quality glass, but usually, that isn't an option as they aren't affordable. Of course, that doesn't mean you can't capture super sharp photos with any other lens, it just helps to be consistent and efficient.
Be careful when reading MTF charts, but they do provide you with a good idea of the quality glass being used. MTF or Modulation Transfer Function measures the theoretical optical performance of the glass. Read this article here from Nikon USA to learn how to read them.
Autofocus Lens calibration
Sometimes your autofocus needs to be fine-tuned. Not all cameras have the function, but it is something you should look into doing and learn more about. Simply, you need a focus chart (like the one below that I built) and find the setting in your camera for making the adjustment (E.g. AF Fine Tune).
Practice, practice, practice!
Reading is a fantastic way to learn, but not a good way if that's all you're doing. I encourage you to take everything from this article and go out to practice! Experiment with each section and you may be surprised to even learn something that wasn't even covered in this article! Even if you practice just on your cat or dog. Assuming you have one. If not, use anything really! Once you're done practicing, review your experience/photos and find out what you did wrong and how you can do better.
Getting crystal-sharp photos is very important, but remember that photography holds its importance as an artistic medium for physical and emotional expression. This just helps you more clearly convey your story when capturing precious moments! Feel free to share this article or contact me with any questions you may have!