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.70D test data on DxO Mark D300S test data on DxO Mark
Rugged construction; 51-point AF system capable of sophisticated AF tracking; Large, bright optical viewfinder; 7 fps JPEG or 12-bit RAW burst mode; HD Video capture.
14-bit RAW mode slows continuous shooting from 7 fps to 2.7 fps; Somewhat slow AF for a camera at this level, especially in 51-point auto-area mode; Video capture tops out at 720p24.
Dual Pixel CMOS AF delivers full-time continuous autofocus (with phase detect at every pixel in framing area) for video and Live View still shooting; Full HD (1080p) video recording with pro-level features and quality; Improved resolution and good high ISO performance; Excellent Wi-Fi remote shooting with full exposure controls; 3-inch articulating LCD touchscreen.
Image quality only improved slightly over 60D; Dynamic range still lags behind competing models; May not feature enough upgrades to convince people to step up from 60D.