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.ZS100 test data on DxO Mark P7800 test data on DxO Mark
Excellent image quality for a 1/1.7" sensor; Versatile 28-200mm eq. lens with fast f/2-4 max aperture; Built-in EVF; Fully articulating LCD; Generous set of physical controls; Built-in flash with wireless support; Standard dedicated hot shoe; Full HD and slo-mo movies.
Slow cycle times and buffer clearing with RAW files; Shallow burst mode buffer; Mediocre autofocus speed and shutter lag; Sluggish UI at times; Slow to switch to movie mode; Optical zoom not supported during movie recording when using manual exposure modes; No built-in Wi-Fi.
Compact camera body; versatile 10x zoom lens; relatively good high ISO performance; fast autofocus; many good 4K video and photo features.
Soft lens at longer focal lengths; no tilting display; small electronic viewfinder; slippery finish on the camera body.