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.K-5 IIs test data on DxO Mark 7D test data on DxO Mark
Cameras with more dynamic range allow you to take photos with dramatic differences in highlight and shadow areas while retaining detail in both.
Think of a brilliant sunset on a rocky beach: Bright sunset in the background, with dark rocks in the foreground. High dynamic range means more of the extremes will be faithfully reproduced.
Dynamic range test data courtesy of DxO Mark.K-5 IIs test data on DxO Mark 7D test data on DxO Mark
Excellent 18-megapixel sensor with impressively low noise and superb detail; Very good high ISO performance, especially for 18-megapixel subframe sensor; Rugged construction with magnesium body and weather sealing; Fast autofocus and fast burst rate of 8 fps; Full HD (1920x1080) movies at 30/25/24p, 60/50p at 1280x720.
No dedicated AF-assist lamp (flash is used), and AF-assist adjustment is buried in the Flash Settings menu; Kit lens (28-135mm) isn't quite up to the resolving power of the 18-megapixel sensor, odd focal length for subframe DSLR; No continuous autofocus in Movie mode.
Noticeably better sharpness than standard K-5 II; Compact yet control-rich body packs in the features; Updated autofocus system focuses in near-darkness; Fully weather-sealed; Very good dynamic range; In-body image stabilization; Dual-axis level with horizon correction.
Prone to moire, aliasing, and false color artifacts; Can seem intimidating at first; Fewer autofocus points than competitors; Doesn't take advantage of high-speed UHS-I flash cards; Movie feature set is very dated and file sizes huge.