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.FZ70 test data on DxO Mark FZ300 test data on DxO Mark
Good image quality for its class; Improved ergonomics; Impressive new EVF and rear display; Versatile 24-600mm equivalent f/2.8 lens; Faster autofocus performance; 4K video and 4K Photo features.
Bulky camera body; Excessive default noise reduction applied at lower ISOs; Continuous autofocus performance is inconsistent.