[asp1880]

When I got the K-5 a year ago, the lens corrections blocked the camera the same way they
did on the K-x. Meaning the buffer was reduced to 3 or 4 shots and you couldn't chimp or
enter the menus while the camera processed. You could still alter exposure and shoot
though, buffer permitting.

Since then I've upgraded the firmware and I'm now on v. 1.12. I've just noticed that
the lens corrections no longer limit the buffer or block the menus! Excellent. Only image review
is still blocked, I get the hourglass when pressing the playback button. Everything else
is now accessible while the camera processes in the background, periodically flashing the
red card access light.

I just thought I'd share this discovery. Lens corrections have something of a bad reputation
for "slowing down the camera". Well, that's no longer as true as it used to be.

Regards,
--Anders.

[Eulogy]

It's still true, though not nearly as bad. Honestly, if you're shooting RAW, you'll deal with 10x the delay as an in camera corrections.

[Schmidlapper]

I also have recently begun using the in camera lens correction when shooting. I especially wanted it after investing in several DA Limiteds, 15, 35 and 70. I generally shoot landscape and still life type shots anyhow so am normally in no hurry. It is good to know that there has been improvement made and delay has been reduced. I was looking at buying software to correct lens issues and remembered that I could just turn it back on in the camera, so I did and now I have Pentax engineered correction right in my raw file. If you turned it off due to slow down, as the original poster mentions with the latest firmware improvement it may be worth revisiting.