How can I take sharper photos?
How can I take sharper photos?
There are many things that you can do to improve the sharpness of your images, however, you will achieve 90% of the results by getting just two things right: shutter speed and focus.
Let’s start with shutter speed. You need a fast enough shutter speed to freeze any motion that occurs during your exposure. There are two things that may move during your exposure: your camera (called camera shake) and your subject (motion blur).
Eliminating camera shake
If your camera moves during your exposure, the entire picture will be blurry.
When you use longer focal length lenses, camera shake is amplified because a small movement of your camera equates to a large movement in the resulting picture. Therefore, as you use longer lenses, you need to use faster shutter speeds. As I have mentioned before, the rule of thumb is to use a shutter speed faster than one over the focal length of your lens. Therefore, if you are using a 300mm lens, you should keep your shutter speed faster than 1/300th second.
If your lens or camera has in-built image stabilisation (or vibration reduction in Nikon-speak) then you have a bit more leeway. You should be able to find out how many extra stops of stabilisation your system provides. For every stop of extra stabilisation you have, you can half the recommended shutter speed. For example, if you have a 300mm lens with stabilisation that gives you an extra 2 stops, then you should be able to get away with a shutter speed of around 1/75th second or faster (i.e. 1/300th halved twice). However, even with image stabilisation, I tend to stick to the rule of thumb as there is little downside to having a shutter speed that is faster than necessary.
The megapixel count of your camera also comes into play. If you have a high resolution sensor, then a small amount of camera shake will be more visible than on a low resolution camera. Therefore, you may want to increase the minimum shutter speed slightly if you are using something like the 36 MP Nikon D810 or the new 50 MP Canon 5DS. The best way to find suitable minimum shutter speeds is to experiment and see what works for you.
An effective way to combat camera shake is to use support such as a tripod/monopod or by resting your camera on a bean bag. These methods can drastically reduce the minimum shutter speed you can use, but they can make framing your shot more cumbersome (particularly if you are using a tripod). While on safari, I typically rest my camera on the side of my vehicle which helps steady it but doesn’t affect my maneuverability too much.
Bonus tip: when hand-holding the camera, a common mistake that beginners make is that they jab the shutter button which causes the camera to move just as the shot is taken. Try to always squeeze the shutter button lightly so that your camera stays steady.
Freeze subject motion
If your subject moves during your exposure, then it will appear blurry. Therefore, you need to have a fast enough shutter speed to freeze its motion. There are no rules of thumb here as your shutter speed will be dictated by the speed of your subject and how large it is in your frame. If you have something that is filling your frame and moving fast, then you will need a very fast shutter-speed to freeze its motion.
For something like a running mammal that is reasonably large in my frame, then I will usually want a shutter speed that is at least 1/1,000th second. Something like a flying bird might need to be even faster, such as 1/2,000th second or more.
This Rhino was charging straight towards me! A fast shutter speed of 1/1,250s helped freeze the motion of the rhino and my trembling hands!
Noise is better than blur
To get fast enough shutter speeds to eliminate camera shake and subject motion, you may find you need to select a high ISO, particularly if you don’t have a fast lens. Increasing ISO means your camera will be more sensitive to light so you can use faster shutter speeds and still get a well-exposed image. Increasing ISO will also result in more noise, but I wouldn’t worry about this too much as noise is better than blur! Here are three more reasons why noise isn’t so bad:
- Noise may be visible when you zoom in to your photo 100%, but when you print or display your images online, it is much less visible. Most people will never get to see your shot at 100% magnification.
- Modern cameras actually have incredibly good high ISO performance so this is much less of an issue than it used to be.
- Photo processing software such as Adobe Lightroom has excellent noise reduction features which can work wonders on your images. This technology is also improving all of the time so sometimes it is possible to go back and “fix” photos that used to be overly noisy.
Now that I have covered shutter speed, let’s consider focus…
Clearly, you need to have your subject in focus for your shot to look sharp. The problem is, as you start to use longer lenses, with large apertures, you get a very shallow depth of field. This means you have to be very careful to ensure that your camera is focusing on the right part of your subject. This can become even more difficult if your subject is moving.
When working with moving subjects or any lens with a shallow depth of field, I recommend using continuous autofocus rather than single shot focus mode. In single shot mode, your focus will be locked when you push the shutter button half-down. In the period of time before you fully press the button, you or your subject may move resulting in a slightly out of focus image. In continuous autofocus mode, the camera will keep adjusting the focus right up until the point at which the photo is taken.
I usually select a very small part of the frame for the camera to focus on (usually a single focus point) and I keep this over my subject’s eye because that is always the part that I want in sharpest focus. Now, in order to frame my shot, I usually need to manually select an appropriate focus point. After a lot of practice, I have become very fast at switching autofocus points so that I can quickly compose my shots while keeping my active focus point over my subject’s eye. Often I may have to compromise a bit and not get the composition quite right, but by leaving a bit of extra space around my subject, I can always crop slightly to perfect the composition later.
My focus point is over the eye, and my camera is in continuous autofocus mode, so that as my boat drifts and the crocodile moves towards me, my camera will adjust the focus accordingly.
The above method is relatively easy if you have a still subject, but when photographing moving animals (or flying birds!), it can be very hard to keep a single focus point exactly over the eye. In this situation I will activate a zone of auto-focus points or all focus points. It then becomes impossible to guarantee the camera will focus on the eyes of the subject. In these situations, there are two things you can do to increase your chances of getting an in-focus shot:
- Use a smaller aperture. Typically, when shooting action, I will use a smaller aperture to give me more depth of field. This will give me more margin for error should my camera decide to focus on some other part of the animal. Try starting with an aperture of around f/8 and then move on to wider apertures as you get more experienced at tracking your subjects.
- Take lots of pictures! When photographing action, I use high speed drive mode on my camera so that when I hold the shutter button down, my camera takes many shots in quick succession. This not only increases my chances of getting the animal in a pleasing pose, it also increases the chances of the camera focusing on the right spot.
Now that you understand shutter speed and focus, you are 90% of the way to getting sharp images. But how can you squeeze that last bit of sharpness out of your gear? Well here’s two more areas you should understand…
Image sharpness is very dependant on your camera lens. Here are some things to consider when selecting a lens:
- There is no getting around the fact that quality lenses produce sharper results. This is one of the perks you are paying for when you buy “pro” glass.
- Prime lenses will usually be sharper than zoom lenses.
- Keep your lens clean as dust or smears on your lens elements can result in softer images.
- Adding accessories to your lens such as protective filters or tele-converters can result in softer images. Some accessories are better than others so I recommend reading reviews from people who have used a particular accessory with your specific lens.
- Understand the characteristics of your lens: lenses will be sharpest at a particular aperture and focal length. DXO labs has a database of lensesand charts that show how well lenses perform at different focal lengths and apertures.
Sharpening your images in post-production can help add that last bit of crispness. This could be a tutorial in itself! Below I have just summarised my process…
Sharpening can be applied locally to parts of the image, such as the eyes. The tool that I use for this is Photoshop. I first create a duplicate layer of my final image and then sharpen it using the “Unsharp Mask” tool. I then apply a black layer mask to the sharpened layer and use a white brush to paint over the areas that I want the sharpening applied to.
If you are going to be sharing your images online, you may want to resize them before uploading. You should apply sharpening after you have resized your images, so that you can tailor your settings for the output display size.