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 A58 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 A58 test data on DxO Mark
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.
Improved 20.1-megapixel resolution; Impressive image quality, especially for its price; Fast and decisive autofocus (in most conditions); Very good battery life; Good video quality (Full HD 1080p, though it doesn't support 60p frame rate).
Plastic lens mount; Slower burst mode speeds and shallower buffer than A57; LCD no longer fully articulating; Mediocre kit lens; Electronic instead of an optical viewfinder may be a turnoff for some.