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.
X100 test data on DxO Mark GF5 test data on DxO MarkSuperb image quality; Dazzling Hybrid Viewfinder; Traditional mechanical controls; Mostly excellent optical performance.
Quirky interface; Manual dials turn easily; Manual focus is too difficult to use; Dramatic lens flare, especially at night.
Small body pairs nicely with compact, retractable Power Zoom lens. Extremely fast autofocus. Worthwhile improvements in image quality. Touchscreen overlays can now be hidden.
LCD panel is prone to fingerprint smudges. Weak flash, and no hot shoe. Modest burst performance, and very limited buffer for raw shooting. Noise levels and dynamic range still lag competition.
