You asked
Is the sigma bf worth it?
Here is what the site says about that.
From Sigma BF: Sigma BF: A mirrorless camera by Sigma with a 24.6-megapixel full frame sensor, announced in 2025. A minimalist body machined from one block of aluminium, with built-in storage instead of a card slot and no viewfinder. Specs - Maker: Sigma - Mount: L-Mount - Sensor: Full frame, 36 x 24mm, crop factor 1.0 - Resolution: 24.6 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: ...
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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