Canon’s entry-level full-frame mirrorless does a lot to appeal to enthusiast photographers, says Andy Westlake, but some might find it over-simplified
Canon EOS RP: Autofocus
Like its other recent mirrorless models, Canon has equipped the EOS RP with its unique dual pixel autofocus technology. This splits every single pixel on the sensor into two photodiodes, facing left and right, which allows on-chip phase detection across practically the entire sensor. In practice you can set the focus area almost anywhere you please aside from the extreme left and right edges of the frame, while a new Spot AF mode allows you to focus precisely on a small area of the frame. One minor disadvantage of dual-pixel AF, however, is that it’s only sensitive to vertical detail, so can hunt in certain situations (the solution often being to rotate the camera slightly until the AF locks).
This year’s must-have feature, however, is eye-detection AF and Canon has now made it available in continuous (or servo) AF mode. It works reasonably well, but it can’t match Sony’s class-leading implementation in terms of ‘stickiness’ to the subject, or the ability to recognise faces across a wide range of angles. Indeed Canon’s version only really works with subjects that are facing the camera almost directly.
In practical use the EOS RP’s AF system generally works well, giving fast, silent and decisive AF with static subjects and making a very decent effort at continuous AF too. As usual for on-sensor AF, it’s inherently accurate, so there’s no need to worry about making micro-adjustments to correct for front- or back-focus with fast lenses. But perhaps its stand-out superpower is its remarkable low-light ability; the EOS RP is capable of focusing with absolute confidence on even the most dimly-lit of night scenes or interiors.
Alternatively, you can use manual focus if the AF fails. But as on its APS-C M system, Canon has employed dubious control logic. With native RF lenses set to AF, full-time manual focus is available, and turning the focus ring will give a magnified view for the most accurate results, which is exactly what we’d expect. But switch the lens to MF and mystifyingly the camera doesn’t engage magnification automatically.
If you’re shooting with the LCD there’s an onscreen touch button to do the job, but for viewfinder work you have to press the AF Area button followed by Info, which is an unnecessarily long-winded process. Worse still, it won’t work if you’ve re-assigned the AF button, for example to DOF preview.