Not easy to find, but there is some hint: Evo 2 Pro camera is equipped with Sony IMX 383 sensor. The same one is used in Sony DSC-RX100 mark VII camera with advertised native ISO as a range 100 - 12800, base ISO 100. Probably that's the value you are looking for. Anyway from various posts it looks that ISO 100 works best in our case.Anyone know?