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.EOS M3 test data on DxO Mark GM1 test data on DxO Mark
Large Four Thirds sensor is impressive for a camera this small; Shares sensor and processor of GX7; Excellent image quality with class-leading high ISO performance; Responsive all-around performer; AF system is fast and accurate; Easy to use and responsive touchscreen; Built-in Wi-Fi with remote control and sharing features; Lightweight and pocketable design makes it easy to carry everywhere.
Can be awkward to use with larger lenses; Rear dial is easy to accidentally press; Lacks a hot-shoe for EVF or external flash; Weak built-in flash; 1/50s flash sync; No 1080p60 video; No external headphone jack or mic input.
DSLR image quality & resolution in a mirrorless body; Higher-res 24MP APS-C sensor; Much improved AF performance; Better ergonomics with full PASM dial; Built-in Wi-Fi & NFC; Tilting LCD.
No built-in EVF; Limited native lens selection; Slow burst mode; Shallow buffer depth with RAW files; No 60p video frame rate or 4K video option.