Sigma fp gets 4K raw output to Atomos and Blackmagic recorders in firmware 2.0: Digital Photography Review
Amazon.com : Sigma fp Mirrorless Digital Camera with 45mm f/2.8 DG DN Contemporary Lens, Bundle with Atomos Ninja V 5" Touchscreen Recording Monitor : Electronics
Atomos Ninja V allows 4k and HD RAW recording in Sigma fp L