Sony a7 IVvsSony a6700: which E-mount body wins

The Sony a7 IV's full-frame sensor gathers roughly twice the light of the a6700's APS-C chip at the same aperture, and it packs 33 MP against 26 MP. That shows up as cleaner files at high ISO and more room to crop a frame and still print large. Its native range also reaches ISO 51,200 versus 32,000 on the a6700; anything above that on the a7 IV requires expanded ISO settings, which trade dynamic range for brightness.

Stabilization is close, and the a7 IV's 5.5-stop figure was measured with a specific test lens attached, so treat the half-stop lead as small. If most of your shooting happens indoors, at dusk, or with fast primes, the full-frame body earns its price. In bright daylight the gap narrows to almost nothing.

The Sony a6700 is the stronger video tool for frame rates. It records 4K at up to 120 fps, though that top rate uses a crop, while full-width 4K reaches 60p. The a7 IV caps at 30p across the full frame and only hits 60p once you switch to a Super35mm crop, which throws away much of the sensor's size advantage.

Both offer 10-bit color and log profiles, so grading headroom is broadly similar, with the a7 IV claiming 15 stops of dynamic range in S-Log3 against 14 on the a6700. Neither records raw internally or externally. For slow motion and hybrid work, the smaller body simply gives you more usable frames straight out of the camera.

The Sony a6700 recognizes more subject types: humans, animals, birds, insects, cars, trains and airplanes, where the a7 IV covers humans, animals and birds. If you shoot motorsport or aircraft, that wider detection list is a real usability difference rather than a marketing line.

Burst speed is a wash in practice. The a6700's 11 fps edges the a7 IV's 10 fps, but the a7 IV only holds 10 fps with compressed RAW, JPEG or HEIF and drops to 6 fps for lossless or uncompressed RAW. If you need maximum detail per frame, the smaller camera holds its rate better. The a7 IV answers with a 1/8000 s mechanical shutter against 1/4000 s, which helps in bright light with fast glass.

The a7 IV has the better viewfinder by a clear margin: 3.69 M dots at 0.78x magnification versus 2.36 M dots at 0.7x. That matters for manual focus, for framing telephoto shots, and for anyone who spends long sessions with the camera to their eye. Both rear screens articulate fully and sit at the same resolution, and the a6700's panel is nominally a touch larger.

The a7 IV also gives you two card slots, which means backup or a dedicated video card, plus a full-size HDMI port instead of micro. It is dust and drip resistant but not IP-rated, and Sony publishes no weather-sealing figure for the a6700 at all. If you shoot in rain or dust, only one of these has any stated protection.

Battery life is effectively identical: 580 shots per charge on the a7 IV through the rear LCD and 570 on the a6700, so neither will strand you on a day out. The real split is bulk. The a6700 weighs 493 g and is noticeably shorter and narrower, which is the difference between a camera that lives in a bag and one that gets left at home.

The a7 IV is deeper from grip to monitor than the a6700, though Sony's own total-depth figure is larger than that measurement. Both charge and take power over USB Type-C, both have headphone ports, and both are rated down to 0 °C. The a6700 is the one you carry all day.