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.D4S test data on DxO Mark 5DS R test data on DxO Mark
Cameras with longer battery life can take more photos before exhausting their batteries.
Excellent, tank-like build quality; First-rate ergonomics a pro would expect; Superb performance with confident autofocus; Great image quality; Big, bright viewfinder with 100% coverage; Excellent battery life; Doubles as a powerful video capture tool
Fairly minor upgrade over the D4; Image quality improvements apply only to JPEG; XQD card format isn't broadly accepted; Consumer-friendly default JPEG processing may turn off some pros; Body is large and hefty (but that's normal for pro gear)
Phenomenal resolution and sharpness; Fine Detail Picture Style is like in-camera Unsharp Mask; Excellent print quality; Decent high ISO performance; Improved normalized dynamic range compared to 5D Mark III; Decent burst speed with good buffer depths; Built-in intervalometer & timelapse movie mode.
AF speed tested closer to consumer-level DSLRs; Dynamic range lower than competing models from Nikon & Sony; Lack of OLPF means subject to more aliasing artifacts with some subjects; No 60p video frame rate; No headphone jack; Timelapse video is only 1080p.