Originally posted by Laurentiu Cristofor Are you sure? From what I understand, the corrections are automatically applied in JPEG. That's how photozone can show results with and without correction. If they were applied in RAW, they would not be able to test the uncorrected images. And these corrections don't exist for all lenses either - they are lens specific.
They are pretty much like the lens corrections you can apply on Pentax DSLRs and you have control over them in the RAW editor, just like with the Pentax RAW files.
OTOH, Pentax cameras do some auto NR at high ISO which you cannot prevent in RAW files, so the practice of RAW files not being RAW was initiated by them.
Yes, the major commercial RAW converters (ACR, Lightroom) process the correction meta-info on import. Not all RAW converters do though, so that's how uncorrected files are attained, by using lesser known RAW converters that don't have deals with the manufacturers.
Yes Pentax does lens correction now but's that's a relatively new thing and not such an integral part of its image quality. The K mount was from a time when engineers worked very hard to get the very best quality out of their optics. There was no such thing as auto-correction for film.
Pentax FA lenses are full-frame, meaning that APS-C gets the "sweet spot" of lenses made for a significantly bigger 'sensor' (35mm film). Edge to edge to quality, vignetting, and distortion all benefit from the 1.5x crop factor. DA lenses were made especially for APS-C digital sensors with mirrors in front of them. This meant making the rear optics of the lenses telecentric, bending the incoming light to be as perpendicular to the sensor as possible vs. at an angle, which digital sensors capture much less efficiently than film.
Micro 4/3rds and Sony NEX were designed from scratch in the digital age with digital lens correction baked into the design from the beginning. Their priority was thinness and flange distance, making the incoming light come in at extreme angles depending on the focal length. The very first m4/3rds cameras and NEX sacrificed optical quality for size of both lens and camera, and the uncorrected files prove just how much they've always relied on digital correction. See DPreview's thoughts on the Sony NEX lenses in particular, and ask yourself why all the good ones are so massive.
The K-01 will rely much less on digital correction vs. true optical quality than the other mirrorless mounts precisely because of it's 'legacy' K-mount. (In fact I'm not even sure there's even an option to correct FA lenses)