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.A35 test data on DxO Mark FZ1000 test data on DxO Mark
Extremely compact compared to interchangeable-lens camera with similar lenses; Comfortable grip and controls; Bright, far-reaching 16x zoom lens; Excellent electronic viewfinder; Versatile tilt/swivel LCD; Excellent performance; Great image quality
Body materials feel a bit plasticky; Connector compartment door is fiddly; Limited raw buffer depth; Battery life below average for class; No built-in neutral density filter