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.A37 test data on DxO Mark RX10 test data on DxO Mark
Smaller than SLR/CSC with comparable lenses; Larger sensor than other bridge cameras; SLR-like body without the hassle of changing lenses; Weather-sealed; Constant f/2.8 maximum aperture; Generous zoom range; Great viewfinder; Swift performance; Plenty of enthusiast-friendly features including raw shooting; Wi-Fi and NFC wireless sharing.
Expensive compared to other bridge cameras; Menus respond slowly after burst shooting; Lens doesn't zoom very quickly; High ISO performance doesn't quite match RX100 II.