Sigma 90mm f 2 8 dg contemporary vs sony fe 100mm f 2 8 stf gm oss?

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From Sony FE 100mm f/2.8 STF GM OSS: Sony FE 100mm f/2.8 STF GM OSS: A prime lens by Sony for Full frame cameras, 100mm f/2.8. Its apodization filter makes very smooth out-of-focus backgrounds, at the cost of light (T5.6). Specs - Maker: Sony - Focal length: 100mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Sony E - Stabilised: yes - Autofocus: yes What it frames like - On full frame (Sony E): as marked, 100mm. - On APS-C ...

From Sigma 90mm f/2.8 DG Contemporary: Sigma 90mm f/2.8 DG Contemporary: A prime lens by Sigma for Full frame cameras, 90mm f/2.8. Specs - Maker: Sigma - Focal length: 90mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Sony E, L-Mount - Stabilised: no - Autofocus: yes What it frames like - On full frame (Sony E, L-Mount): as marked, 90mm. - On APS-C (Sony E, L-Mount): like 135mm on full frame; f/2.8 gives about the ...

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