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.LX100 test data on DxO Mark RX100 test data on DxO Mark
Excellent high-ISO performance for such a compact model; Smart controls; Small body; Bright lens; 10fps full-res burst mode; Very fast shutter response; Excellent LCD.
Lens flare at night; Poor rendering of yellows; Slow flash recycling; Soft corners wide open; Continuous AF mode slow to lock.
Very good image quality; Great performance in most respects; Bright zoom lens with good macro performance; Photographer-friendly body easily fits in a coat pocket or small bag; Roomy, high-res built-in viewfinder; Decent battery life
Won't fit in a pants pocket; Relatively low resolution by modern standards; Zoom lens has only a modest telephoto; Soft corners at wide or tele positions; Aperture dial is too easily bumped; Bundled flash is fairly weak