You asked
Is the yongnuo yn12 35mm f 2 8 4m worth it?
Here is what the site says about that.
From Yongnuo YN12-35mm f/2.8-4M: Yongnuo YN12-35mm f/2.8-4M: A zoom lens by Yongnuo for Micro Four Thirds cameras, 12-35mm f/2.8-4. Specs - Maker: Yongnuo - Focal length: 12-35mm (zoom) - Maximum aperture: f/2.8-4 (it gets darker as you zoom in) - 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 24-70mm on full frame; f/2.8-4 gives about ...
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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