Originally posted by nocturnal I don't believe the ISO 'raise' works though in practical terms, 12800 is impractical for my photography without needing 25600 anyway. I think true high ISO improvements requires better hardware (electronics to boost the signal that is collected). Probably the K50 marketing department thought of the ISO boost and then went silly with the ISO claims of the Pentax KP!!!
12,800 ISO may be impractical to you, however, the 25,600 ISO was already available on the K-30 (you need to enable expanded ISO in the custom settings menu).
All the K-50 firmware did was make the ISO native instead of having to go into a menu to enable the extra value.
I've shot at 10,000 ISO at an indoor theatrical event and the client loved it. Good detail and dynamic range for limited ambient lighting.
I do agree, that not everyone shoots or has the need to shoot at such high ISO's but I don't find it impractical, I've actually been glad it was available.