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.GF5 test data on DxO Mark J4 test data on DxO Mark
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.