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Best camera for the sigma 50 120mm f 2 8 dc os contemporary?

For the Sigma 50-120mm f/2.8, I'd start with an APS-C body. On Sony E or Fujifilm X it frames like 75-180mm, and its f/2.8 gives about the depth of field of f/4.2. Some good matches:

If you already own a full-frame body such as the Sony a7 IV, the lens still fits and works in APS-C crop mode, though at fewer megapixels. Check the lens page for the full list of compatible bodies.

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