Get sharper shots, longer reach, beautiful blur and more
A good lens will stand the test of time far more than the latest camera body, but are you making the most of your favourite glass? Let's look at 10 tips to ensure you get the best out of your lenses...
1 Find the sweet spot
All lenses have a sweet spot. This is the aperture value that will result in the sharpest shot.
Most lenses will be slightly softer when the max aperture is used. The sweet spot is usually a stop or two down from the max aperture around f/5.6-f/8. It’s worth spending the time to find the sweet spot in your favourite lenses. Take test shots while varying the aperture to determine yours. As well as extra sharpness, it’s also the point where chromatic aberration is at its lowest, so colour fringing along edges will be kept to a minimum.
2 Use teleconverters and extension tubes
As photographers we almost always have our eye on another lens, a faster prime or a longer zoom. But we might not necessarily need to fork out for a shiny new lens, instead we may be able to make use of those already in our kit bag. If you need extra reach then a teleconverter can let you double your focal length.
The trade-off is that the max aperture will close down by a stop or two and sharpness may be slightly reduced, but it can still be a great way to modify your existing lenses. Another great modifier is an extension tube, which can get you closer to macro subjects by decreasing the minimum focusing distance, thereby enabling you to fill the frame with the tiniest of details.
3 Don’t rely on autofocus
Autofocus is a great aid, but it’s worth practicing focusing manually as there may be times when the autofocus struggles. You can make use of in-camera focusing aids like focus peaking (which overlays coloured lines along edges in the scene to show what’s sharp).
It’s also worth checking that your autofocus is spot on, as a surprising number of lenses will front or back-focus slightly, which can ruin your shots by leaving them slightly soft. You can check for this by photographing a ruler at an angle. Most cameras have a micro focus adjustment tool that lets you shift the focus point forwards or backwards in tiny increments to correct for any misalignment.
4 Shoot wide open
Shooting wide open results in a wonderful shallow depth of field with a tiny plane of focus, and everything but the point of focus will dissolve into beautiful blur. It means using the widest possible aperture, which is typically around f/4 with a standard zoom or wider with a prime lens, so this is where prime lenses like a 50mm f/1.8 come into their own.
Use aperture priority for this and set the max aperture, then let the camera work out the appropriate shutter speed. Of course, when the plane of focus is so miniscule you need to be very precise with focusing, as even the slightest shift forwards or backwards will throw the focus off. So switch to single point focus and shift your focus point around the frame until it sits directly over the subject. For portraits, focus on the eye that’s closest to the camera.
5 Multiple-use lenses
A lens may be designed for one type of subject, but that doesn’t mean it can’t excel in other shooting conditions too. Macro lenses, for example, are often designed with a focal length around 90-105mm. As well as being suited to close-up subjects, this is also a great focal length for portraiture (a dedicated portrait lens is usually around 85mm). Macros also tend to have great sharpness, wide max apertures and lovely bokeh, which are also ideal lens features for shooting portraits.
6 Zoom with your feet
If you want to get closer to your subject, then the instinctive thing to do would be to zoom in. But sometimes you might be better off changing your shooting position instead. Try shooting at one focal length for a day, and zoom with your feet instead.
This will give you a different perspective and change the angle of view, which may result in a more interesting shot. It also means you might not need to take out a long heavy lens.
Conversely, sometimes it might be better to move a few steps further away from the subject and zoom in. This compresses the perspective, gives a tighter angle of view and emphasises background blur, which is ideal for separating the subject from the background.
7 Correct distortion and fringing
No lens is perfect, they all have their own distinct imperfections. Barrel distortion can cause straight lines to bend slightly, especially at wider focal lengths around the edges of the frame. Vignetting can cause the corners of the frame to darken slightly, and the corners can also be slightly softer than the centre of the frame.
Lens correction tools like those found in Lightroom can help to correct for this. DxO software is also very adept at correcting imperfections. It calls upon a huge database of lens-camera combinations to fix common issues.
8 Cut out flare... or shoot for it
Lens flare can cause the image to go hazy and soft. It occurs when strong light shines into the lens. One way to prevent it is to use a lens hood. You can also shield the front element of the lens from direct sunlight with your hand or a piece of card. Sometimes a little lens flare can enhance the atmosphere, so there may be times when you want to let the sunlight hit the front of your lens. You can even manufacture your own flare by reflecting sunlight onto the glass, or by holding a prism or old CD up close to the lens.
9 Know when to use stabilisation
Lens stabilisation is hugely useful when hand-holding the camera, as it lets you get away with slower shutter speeds (especially if it’s working in combination with in-camera stabilisation in modern mirrorless cameras).
"...if you’re using a tripod then there’s no need for extra stabilisation, so turn it off"
This is especially useful when using longer lenses as any slight movement is exaggerated, which may cause shake and ruin the shot.
However, if you’re using a tripod then there’s no need for extra stabilisation, so turn it off. In fact, the lens stabilisation may actually cause tremors when shooting on a tripod, as the system can become confused and hunt around for movement.
10 Prevent diffraction
Smaller apertures mean that more of your scene will be in-focus. So you’d assume that this will give you sharper shots. But this isn’t necessarily true. As the f/stop value gets higher, the aperture becomes smaller and the light waves travelling through begin to interfere with one another, resulting in softer details. This is called diffraction, and it affects all lenses to some extent, although it’s less of a problem on low-resolution cameras. Diffraction usually becomes more prominent beyond f/16, and you may see obvious softness in the fine details at f/22 or more.