Maximum effective ISO is an estimate of the highest sensitivity at which a camera can capture excellent quality photos.
Cameras with higher effective ISO will be better choices for indoor photography, night shooting, and indoor sports photography, especially if you intend to make large prints.
You can learn more at our glossary entry.
Maximum effective ISO test data courtesy of DxO Mark.ZS100 test data on DxO Mark RX100 III test data on DxO Mark
Pocket-friendly design; Popup electronic viewfinder; Bright lens across the zoom range; Great performance with very fast autofocus; Very high resolution gives lots of detail in good light; High ISO noise levels much better than most pocket camera rivals; Wi-Fi wireless networking
Feels a little unbalanced without an accessory grip; Not as much telephoto reach as its siblings; Noise processing is heavier-handed than in earlier models; Quite pricey for a fixed-lens camera
Compact camera body; versatile 10x zoom lens; relatively good high ISO performance; fast autofocus; many good 4K video and photo features.
Soft lens at longer focal lengths; no tilting display; small electronic viewfinder; slippery finish on the camera body.