Panasonic Lumix DMC-GX7 review – Autofocus
Since the G1’s inception, Panasonic has worked hard to improve the focus-acquisition speed of its CSCs, and with the GX7’s new image sensor and Venus Engine image processor, a data readout time of 240fps is possible with the company’s Light Speed AF technology. This translates to a focus speed of around 0.06secs, and in tests it’s hard to dispute this. I found the GX7 promptly acquired focus without hesitation in most conditions, while those shooting in poorly lit, low-contrast situations will welcome the camera’s low-light AF. This sees the GX7 capable of focusing in lighting conditions as dark as -4EV (roughly equivalent to starlight), something even advanced DSLRs would struggle with. It didn’t disappoint either, impressing with its ability to lock on to subjects in dimly lit conditions that would normally result in focus not being achieved, though it is not quite as snappy as in general use.
Autofocus coverage is very good, and it is possible to select anywhere in the frame to focus. For quick focus selection when using the GX7’s 1-area focusing mode, I found using the touch-sensitive display preferable and considerably quicker than manually moving the focus area round the screen with the four-way D-pad.
If you need to be absolutely precise with focusing, the GX7’s pinpoint AF mode allows you to do just that, and features a picture-in-picture display so you can retain framing while confirming focus on the magnified area of the image. There’s the choice of either 3x or 6x magnification, and I found it a great tool for those occasions when correct focus was critical.
