You asked
Is the ttartisan 90mm f 1 25 good in low light?
Here is what the site says about that.
From TTArtisan 90mm f/1.25: TTArtisan 90mm f/1.25: A prime lens by TTArtisan for Full frame cameras, 90mm f/1.2. Specs - Maker: TTArtisan - Focal length: 90mm (prime) - Maximum aperture: f/1.2 - Made for: Full frame sensors - Mounts: Sony E, Nikon Z, Canon RF, L-Mount, Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Sony E, Nikon Z, Canon RF, L-Mount, Leica M): as marked, 90mm. - ...
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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