Originally posted by THoog The K-01 holds the lens wide open until firing the shutter to provide more light for focusing (this is a feature of all K-mount cameras, going all the way back to the 1970s). Because of this, unless you are shooting with the aperture wide open, what you see is NOT what you will get, exposure-wise. I understand what you are looking for, but it's the opposite of one of the fundamental features of a K-mount camera.
The one tweak that Pentax did add is that it will automatically stop down to protect the sensor if the light gets too bright (I call it 'squinting' - some people complain about hearing it while walking around). This is another case of what you see is not necessarily what you will get.
This is one of those "It's not a mirrorless camera with a K-mount - it's a K-mount camera without a mirror." things.
Thanks for such an informative reply.
The problem is that it's not the 1970's. It made sense to operate as you described when a preview of the real captured exposure was impossible. On modern cameras though it forces us to pretend we are unable to see an exposure preview and it cripples the camera vs. the competition.
To clarify - the behavior of the camera can remain the same. The exposure is calculated for the screen, it doesn't have to be actual. The lens can remain open but when we set it to F22 the processor can calculate the loss of light and adjust the displays accordingly if desired. This has no effect of focusing and is how I believe the Canon's do it.
Pentax is not alone in this. We are still stuck in a film-based paradigm and manufacturers are being very slow to realize the old restrictions don't apply. Focus peaking is the easiest example. It makes using manual focus better than it ever was. It would be great to see Pentax embracing firmware updates as a way of adding value.
I also hope there's a K01 firmware project underway.