Photography News Issue 66

Photography News | Issue 66 | photographynews.co.uk

Techniques 16

It is what it is

Focus group

There’s nothing that a mirrorless camera inherently does to make a better exposure, but because of the way an electronic viewfinder works it does let you see exactly what your exposure settings are giving you before you shoot. The EVF is giving you a live feed from the sensor so any changes you make will be clear, assuming you’ve switched that mode on. And it’s not just exposure. You get accurate colour, depth-of-field, composition and focusing peaking, along with exposure tools like live histograms and ‘zebra’ style highlight warnings. Yes, you can get these on a DSLR’s screen in live-view mode, but it’s not the same as having them right there in the viewfinder. One of the biggest benefits of using an EVF is when working in tricky lighting conditions, like a backlit portrait, or a snow scene. So while you’d still need to apply some exposure compensation or manually alter the exposure to improve the shot, with an EVF you can see the brightening or darkening and therefore perfectly judge its effect. An electronic viewfinder can mean more accurate exposures and enhanced creativity

Mirrorless cameras’ AF performance can be faster andmore reliable thanDSLRs

Because they dispense with the mirror box of a DSLR, and focusing takes place directly on the sensor, locking on to subjects can be a lot quicker with mirrorless cameras. On DSLRs, the mirror channels the light into the optical viewfinder and on to an AF sensor, and after calculations are made, the mirror has to get out of the way before a picture is taken to reveal the sensor. No mirror means that AF is faster. If you add features

like the Sony A9’s revolutionary stacked sensor it gets even better. Using the sensor for AF also means more of the frame is available for setting as an AF point, even right up to the edge. And because most mirrorless cameras use a mix of contrast and phase-detect systems, you get advanced modes like face and eye recognition. And if you’re focusing manually, you can use focus peaking right there in the viewfinder.

Silent right

Speed is king

As quiet as manufacturers try to make the mirror and shutter mechanisms of DSLRs, there’s only so far they can go, and the noise they make can still be off-putting in some situations like weddings, concerts, and street photography. The sound of a shutter can even make people nervous in portrait sessions. On a mirrorless camera, there are no such worries, as the lack of a moving mirror immediately cuts down noise. And on top of that, mirrorless cameras can shoot with a purely electronic shutter for totally silent operation – DSLRs can do this too, in their live-view modes, but not in such a sophisticated way. The benefit of electronic shutter goes beyond silence, too. If you’re shooting multiple exposure techniques like focus stacking and timelapse, the shutter doesn’t need to open and close, which it can only do a certain number of times before it breaks, so your camera will live longer. Mirrorless cameras are better suited to silent shooting than DSLRs, and that has all sorts of benefits

Mirrorless means blistering frame rates

When you take the traditional mirror mechanism out of a camera you can also increase the speed of shooting. Simply put, if you want to retain AF and autoexposure through a burst of images, a DSLR will need to push and pull the mirror out of the way between each one, and there’s a physical limit to how quickly that can be done. Pro- spec cameras like Nikon’s D5 will give

you 12fps with AF and AE, and 14fps with the mirror locked up, wherein exposure and focus is also locked. The Canon EOS 1D X Mark II can shoot up to 14fps with full AF and AE. But as fast as those speeds are, you also get blackout between frames, which makes following the subject difficult. On a mirrorless camera the only restriction in frames-per-second is

how quickly the camera can calculate focus and exposure and push images through to the card. Theoretically there’s no limit. With the Sony A9 for example, you’re looking at 20fps with full AF and AE function, and with no viewfinder blackout at all. Other cameras like the Olympus OM-D E-M1 Mark II can shoot at up to 18fps with autofocus and 60fps with single focus.

Next month: We look at the superb buying options out there for mirrorless bodies and lenses.