Color depth refers to the number of unique colors that a sensor can faithfully capture. Cameras with better color depth will demonstrate smoother transitions from one color to the next, and avoid "banding" in areas with subtle shading. (Blue skies are an example of where you might see color banding.)
More color depth is generally better, but you'll struggle to notice a difference between two cameras with less than 1 bit of difference. Color depth above 22 bits is considered excellent.
Want to learn more? Head over to our full glossary entry on color depth
Color depth test data courtesy of DxO Mark.RX100 IV test data on DxO Mark Q test data on DxO Mark
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.RX100 IV 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.RX100 IV test data on DxO Mark Q test data on DxO Mark
Cameras with longer battery life can take more photos before exhausting their batteries.
Special note: The measurement standard for battery life stipulates that if a camera has an internal flash, it must be used for 50% of photos taken. For this reason, comparisons of one camera with an internal flash to another without will not be comparable
The first genuinely compact--almost pocket-friendly--compact system camera, paired with equally small, interchangeable lenses. Great ergonomics for the size, and it feels like a real camera, not a computer with a lens.
Very restrictive lens selection at launch. All but two current lenses have severe limitations in functionality. Performance is sluggish, and image quality trails large-sensor cameras by some distance.
Vastly improved burst speeds with deep buffer; Great performance with very fast autofocus; Very high resolution gives lots of detail in good light; High ISO noise levels much better than most pocket camera rivals; High-quality 4K video with uncompressed HDMI out; Super-fast High Frame Rate video; Same great pocket-friendly design.
Pricey for a compact camera; JPEGs can look over-processed at higher ISOs; Lens doesn't offer as much telephoto reach; Battery life not as good as predecessor; 24-70mm-equivalent lens can feel limiting.