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.E-M1 test data on DxO Mark RX10 II test data on DxO Mark
Exceptional rugged, weather-proof, professional build; Lightning fast contrast-detect AF, and phase-detect AF that makes Four Thirds lenses far more responsive; Tons of useful physical controls with immense customizability; Arguably the best image quality of any Micro Four Thirds camera we've tested to date; Large, sharp, high-resolution electronic viewfinder; Advanced Wi-Fi capabilities, including remote control shooting in PASM exposure modes.
Bigger and heavier than many other compact system cameras; Most expensive Micro Four Thirds camera on the market to date; Menu system and customization options have a steep learning curve; No optical low-pass filter means greater risk of moire; No built-in flash.
Excellent build quality; Superb viewfinder; Excellent image and video quality for its class; Bright and versatile zoom lens; Very fast autofocus; Great burst performance and depth; Incredible slow-motion capabilities; Really intuitive Wi-Fi image transfer; Good battery life.
Expensive compared to its nearest competitors; Less zoom reach than rivals; Soft in corners wide-open; Slow buffer clearing; Small rear control dial has poor tactile feedback; Long delay to render each high frame-rate movie; No tilt/swivel or touch on the LCD panel.