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 RX100 II test data on DxO Mark
New, 20.2MP, 1-inch type, backside illuminated (BSI) image sensor produces superb image quality, with particular improvements in low light and high ISO; 3-inch tilting rear LCD screen handy for composing shots from difficult angles; Fast all-around performer with quick autofocus and virtually no shutter lag; New, multi-interface hotshoe for adding a strobe or optional electronic viewfinder; Built-in Wi-Fi with NFC.
Bigger and heavier than previous model; More expensive than previous model; Reduced burst performance when shooting RAW files; Somewhat confusing menu structure and control layout; Wi-Fi features can be difficult to set up.
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.