Lens performance

The Sony RX10 IV uses the same 24-600mm F2.2-4 equiv. zoom lens as its predecessor, the Sony RX10 III. Below is our lens widget and analysis from the RX10 III review comparing its lens performance to that of other 1-inch superzooms in its class.

The infinity shootout

Starting at the wide end, which is around 25mm for all the cameras tested, we see in the center of the image (where our RX10 II appears to perform as expected) improvements over the RX10 II aren't incredibly pronounced. Other areas of the scene show the advantage of the RX10 III, especially when it is stopped down from its maximum aperture of F2.4 to F2.8. Its performance is definitely a step up from the Panasonic FZ1000, and is miles ahead of the Canon G3 X.

Where crazy zoom lenses like these typically struggle is in the extremes of the frame, with neither the RX10 III or the FZ1000 being an exception. The sharpness fall-off is less severe with the RX10 III, though, and all in all, the RX10 III is the best performer on the wide end.

Moving on to 400mm, the maximum focal length for the Panasonic FZ1000, we see a similar amount of detail between the Panasonic and Sony near the center of the image. Sharpness and resolution change for both throughout the frame, with the Sony showing a slightly iffy left side, and a better right side. Through most of the scene the two are practically neck and neck, with the G3 X turning in comparable performance as well, but let's not forget the Sony and Canon still have more zoom range to go.

The RX10 III's 24-600mm lens isn't only useful for distant details.

The real reason people consider bridge cameras is for the reach, and Sony extended the RX10 III's reach by a full 400mm over the RX10 II. That means it now offers the same amount of reach as the G3 X's 600mm equivalent maximum focal length. The RX10 III's lens is clearly sharper, but it has another thing going for it: its faster maximum aperture helps it combat diffraction. Remember that F4 and F5.6 on 1"-type cameras are equivalent to F11 and F15, respectively. Both cameras are limited by atmospheric distortion at these focal lengths (hence the drop to 'print' resolution in the previous comparison link), but it's clear that the RX10 III exceeds the G3 X's performance, while offering just as much zoom versatility. The Canon PowerShot G3 X's trump card has been trumped.

Even at 600mm (equiv), the Sony Cyber-shot RX10 III's lens delivers sharp results.

In all, it seems the RX10 III does offer a bit more than similar 1" bridge cameras from other manufacturers. It exceeds, or at least matches, the competition with respect to zoom range, while offering sharper images, and brighter apertures than all but Sony's own RX10 II. Importantly, sharpness performance appears to be maintained throughout the zoom range, from wide to tele, which cannot be said for any of the other cameras in this test. Feel free to explore through these images and post your own findings below.

Reach and speed compared

The RX10 III's lens offers both speed and reach. At the wide end of its zoom, it's around 0.4EV brighter than its 1"-type sensor rivals. At 600mm equivalent it's still able to open as wide as F4, making it a stop faster than the Canon PowerShot G3X while also being significantly longer than the FZ1000, whose zoom only reaches out to 400mm equivalent. If you don't ever shoot beyond 200mm, though, the RX10 I/II have significantly brighter (up to 1 stop) lenses from 35mm all the way to 200mm.

Confused as to what 'Equivalent Aperture' is? Read more about about it here, or jump to our in-depth explanation of equivalence.