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.Z7 test data on DxO Mark SL (Typ 601) test data on DxO Mark
Superb build quality; Amazing EVF; Great image quality from RAW files; Good high ISO performance; Very good dynamic range; Very low shutter lag; Fast AF on stationary objects; Class-leading ~11 fps burst mode; 4K DCI and UHD video; Full HD up to 120p. Built-in Wi-Fi and GPS; Dual card slots; Decent battery life for its class.
Big for a full-frame mirrorless camera; Very slow buffer clearing; Contrast-detect AF system struggles with moving subjects; In-camera JPEGs are muted and dull; Very limited native lens selection (but supports many other Leica lenses via adapters); Expensive.
Familiar design in a compact form; Rugged build quality; Gorgeous EVF; Excellent image quality; Good autofocus; In-body image stabilization; Good 4K video recording.
Single card slot; Not as good at subject tracking as some Nikon DSLR cameras; Limited native lens selection (although adapter works well); Limited buffer depths.