Originally posted by maxxxx Today I took some sunset pictures and as it got darker I constantly had to switch to Bulb mode to get exposures longer than 30 seconds. It's really tedious to have to pull out my intervalometer as it gets darker. I can see that the longer the exposures, the more noise, but it should be up to the user to make that call. Especially in a "Pro" camera like the K-3. And you can get around it with Bulb mode anyway.
Traditionally it's the point where the sensor linearity to light vanishes therefore you can no longer define a correct exposure solution (electronically) for the light available in any generic way that could be applied to every camera made it would need to be calibrated uniquely as each camera came off the production line.
I would assume this is still true as base ISO still hangs out at 100 or 200 so sensor linearity is still a concern for manufacturers