Lens skills
Don’t miss a single shot and understand how your enigmatic lens really works
11 Going long
For Frame-filling impact, you can’t beat the reach of telephoto lens. A subject doesn’t just double in size when you double the focal length: it appears four times as big! They also make background details look larger in frame, and give you more blur as they give you a shallower depth of field. A telephoto lens used at f/4 will give a narrower band of apparent sharpness in a shot than a wide-angle lens used at the same aperture.
12 stay sharp
IF shooting without a tripod make sure the shutter speed is equivalent to the lens’s focal length: 1/200 sec for a 200mm lens. Using an IS (Image Stabilizer) lens can help you get sharper shots at slower speeds, with the latest high-end EF telephoto lenses giving up to 4-stops of support. So, the same 200mm lens could be used at a shutter speed of around 1/13 sec and still create sharp shots in the right hands.
13 Going wide
lenses with short focal lengths in the region of 10-18mm (APS-C) or 16-28mm (full-frame) are capable of capturing pictures that have amazing scale and depth. The trade-off for swallowing up so much of a scene in a single frame is that it’s harder for compositional clutter to creep into the edge of a picture. Get into the habit of running your eye around the viewfinder before you take the shot.
14 Zoom before focus
Most zoom lenses are ‘varifocal’, which means that the focus shifts at different focal lengths. This shift is often not noticeable when you’re using small apertures to give a large depth of field, but it can lead to soft pictures and has the potential to cause problems when you zoom while recording video. So, try and get into the routine of always checking the focus after you’ve zoomed.
15 lens corrections
Canon Cameras come with lens correction controls that enable the effects of optical problems such as chromatic aberration, distortion and vignetting to be automatically corrected. The number of options available varies: the EOS 2000D enables you to correct an image’s dark corners with its Peripheral illumination correction; the EOS 5D Mark IV on the other hand, has a raft of adjustments that can be switched on or off. Each Canon camera is pre-loaded with correction data for a certain set of lenses.
16 aps-c vs full-frame
the Majority of EOS cameras feature APS-C sized imaging sensors. These are smaller than the ‘full-frame’ sensors found in the likes of the EOS 6D Mark II (they’re ‘full-frame’ because the sensors are the same proportions as old-school 35mm film). Because the APS-C sensors are smaller than full-frame, they capture a smaller area of the image that’s projected by the lens. This gives a magnification effect – often referred to as the crop factor of x1.6. Multiple the focal length by this number to get the ‘effective’ focal length when shooting with an APS-C camera.
17 lens hoods
to avoid stray light striking the front element of your lens and causing lens flare, fit a hood. It will also protect the lens when you’re shooting in rain and snow. Not all lenses come with hoods, but they’re a worthwhile investment.
18 Watch out for diffraction
although you might think that the smallest apertures available on your lens will produce sharper results, this isn’t always the case. Lenses produce softer results at apertures such as f/22 and f/32 than they do at f/8 or f/11, so avoid using the minimum apertures unless you absolutely have to.
19 Depth of field
a lens’s focal length, the aperture that’s been selected, and the distance you focus at, all affect the depth of field – or the amount of front-to-back sharpness that’s recorded. To reduce the depth of field and make a subject standout, use a long lens, a large aperture, and focus close. To increase the depth of field and make more of a picture look sharply focused, use a short lens, a small aperture and focus from farther away.
20 DOF preview
the Image you see in the viewfinder of an EOS DSLR is displayed at the max aperture available on the lens. This can make it difficult to gauge the depth of field when a smaller aperture has been set on the camera. The majority of EOS DSLRS, however, feature a depth of field (DOF) preview button near the lens mount (not the lens release). EOS cameras that don’t can have the function assigned to the SET button.