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Sony a7 iii vs sony a7 iv?

Both are full frame mirrorless cameras with in-body stabilisation, so the choice comes down to resolution and age. The Sony a7 III is from 2018 with 24.2 megapixels. It's still a very capable camera, and it's the full-frame bargain if you find one on the used market.

The Sony a7 IV is from 2021 with 33 megapixels. It's the all-rounder, good at stills and at video. If you shoot both, I'd pick the a7 IV.

On either body, the Sony FE 24-105mm f/4 G OSS is a sensible everyday kit lens. If you want something smaller for travel and street, the Sony FE 28mm f/2 is light enough to keep in a bag all day.

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