[Scintilla]

Optical DoF preview on Pentax dslrs is a feature on all older bodies and newer high end models located on the camera's "on" switch. Beginner and mid rage bodies have the option but it has to be set to the "RAW/fx" button.

Drat. I already knew about Optical DoF preview -- and the K-30 doesn't let you take a shot while you're holding the RAW/fx button for it. Oh well, the green button still works...

[Not a Number]

and the K-30 doesn't let you take a shot while you're holding the RAW/fx button for it.

I don't think any of the bodies let you trigger the shutter while operating the DOF preview - my K10D does not. Preview is on the power switch dial.

[Stickler]

I wish Ricoh/Pentax would allow access to truly program functions assigned to the Fx button or similar. This would address many of these issues and aside from the Samsung android camera would be unique. You'd think it would be obvious that the success of the modern smartphone (probably the most successful device on the planet) is due in large part to just such an opening up to uses that the manufacture couldn't foresee or afford to develop. If this was done, consider a couple of interesting "apps" that could be developed:
--Lens database that allows K&M lenses to meter accurately (select lens on startup if Pre-A)
--Allow green button automatically before shutter trip (on Pre-A)
--Camera takes current near focus setting and refocuses to the hyperfocal length (adjusting aperture if so configured)
--Automation of focus stacking capture

Another point on the topic of the couplers (or a software fix to legacy metering) selling cameras, is that this new top shelf camera is competing with more than sufficient cameras that are out there (K-5 and newer IMO) I'm unlikely to upgrade to FF soon, just because of how great and inexpensive recent cameras are, but having this feature would be something that might push some over the upgrade fence. I have a lovely M135 and 28 that I'm sure I'd use more if it did (would be nice if there were equivalent Pentax lenses) this adds one more step (in addition to focusing) that keeps them at home in lieu of a more pragmatic, if less elegant solution. The argument for not supporting legacy lenses falls into the same boat as focus peaking, something that Pentax has included that not all have.

[krazykat]

I wish Ricoh/Pentax would allow access to truly program functions assigned to the Fx button or similar. This would address many of these issues and aside from the Samsung android camera would be unique. You'd think it would be obvious that the success of the modern smartphone (probably the most successful device on the planet) is due in large part to just such an opening up to uses that the manufacture couldn't foresee or afford to develop. If this was done, consider a couple of interesting "apps" that could be developed:
--Lens database that allows K&M lenses to meter accurately (select lens on startup if Pre-A)
--Allow green button automatically before shutter trip (on Pre-A)
--Camera takes current near focus setting and refocuses to the hyperfocal length (adjusting aperture if so configured)
--Automation of focus stacking capture

Another point on the topic of the couplers (or a software fix to legacy metering) selling cameras, is that this new top shelf camera is competing with more than sufficient cameras that are out there (K-5 and newer IMO) I'm unlikely to upgrade to FF soon, just because of how great and inexpensive recent cameras are, but having this feature would be something that might push some over the upgrade fence. I have a lovely M135 and 28 that I'm sure I'd use more if it did (would be nice if there were equivalent Pentax lenses) this adds one more step (in addition to focusing) that keeps them at home in lieu of a more pragmatic, if less elegant solution. The argument for not supporting legacy lenses falls into the same boat as focus peaking, something that Pentax has included that not all have.

Some great ideas here.

Two of the biggest assets Pentax has is its history and its colossal collection of legacy lenses. By better supporting K & M lenses they could potentially add further incentive to woo off-brand users and woo back old Pentax users who have strayed.