Is the yongnuo yn42 5mm f 1 7m ii good in low light?

Here is what the site says about that.

From Yongnuo YN42.5mm f/1.7M II: Yongnuo YN42.5mm f/1.7M II: A prime lens by Yongnuo for Micro Four Thirds cameras, 42mm f/1.7. A cheap autofocus portrait prime for Micro Four Thirds. Specs - Maker: Yongnuo - Focal length: 42mm (prime) - Maximum aperture: f/1.7 - Made for: Micro Four Thirds sensors - Mounts: Micro Four Thirds - Stabilised: no - Autofocus: yes What it frames like - On Micro Four Thirds (Micro Four Thirds): like 85mm on full frame; f/1.7 ...

From Sensor sizes: Is full frame worth it?: For low light, events, and portraits with very shallow depth of field, yes. For travel, street, wildlife on a budget, and most hobby photography, a good APS-C camera with good lenses is enough, and you'll carry it more. Lenses and light matter more than the last stop of sensor performance.

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