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.XF1 test data on DxO Mark ZS40 test data on DxO Mark
Cool retro styling bolstered by a quality build and design; Fast f/1.8 lens at wide angle; Fast autofocus and low shutter lag; Tons of customizability and creative options, including Fuji's special EXR and Film Simulation modes; Full 1080p HD video; PASM controls; RAW still capture.
Special modes have somewhat steep learning curve; Maximum aperture drops quickly as you zoom; Lens cover doesn't lock when storing; Larger sensor doesn't necessarily translate to better photo quality than competitors; Demosaicing errors and moderately high chromatic aberration.