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.A7R III test data on DxO Mark Q 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.A7R III test data on DxO Mark Q test data on DxO Mark
Fantastic image quality; Improved dynamic range over its predecessor; Very good high ISO performance; Much improved real-world AF performance; Class-leading burst rates, even with RAW; Improved 5-axis in-body image stabilization; Better 4K video quality; 1080/120fps video; Dual card slots; Significantly better battery life.
Expensive; Menus still confusing; UHS-II support only on one card slot; No optical low-pass filter means greater risk of moire; No built-in flash; Buffer clearing still slow despite UHS-II support.