Boris, The blinkies in the camera are with respect to the JPEG preview, not the RAW file. They blink at 255 (maximum 8 bit value) but that 255 is mapped to an arbitrary value on the actual scale from 0 to 16383 with 16383 being the actual maximum value. The blinkies in LR are with respect to the result of the rendering settings as applied to the RAW data, not the actual RAW data itself.
What you are actually doing in Lightroom when you alter the exposure is shifting the mapping of the JPEG (or display) rendering's 0-255 values to the RAW file's 0 to 16384 range (note that one value on the 0-255 scale will be mapped to multiple adjacent values on the 0-16383 range of the RAW file). When you are adjusting exposure in LR, you are shifting the mapping up and down the RAW file's range (other controls alter the mapping inside that range or alter the 255 or 0 point mapping independently). -Adam On Sun, Nov 7, 2010 at 9:53 AM, Boris Liberman <[email protected]> wrote: > Adam, Ralf, if I understand you correctly, it means that overexposure > blinkies of both my camera(s) and LightRoom actually start blinking not at > pixel value of 255 but somewhat prior to that. And then, you and also Adam > say that whatever the minus exposure compensation I am dialing in in > LightRoom to make those red blinkies disappear has nothing to do with actual > sensor dynamic range? Is that so? > > Boris > > > On 11/7/2010 4:22 PM, Ralf R. Radermacher wrote: >> >> Boris Liberman<[email protected]> wrote: >> >>> What you say, Tim, makes perfect sense. But outside of Pentaxia, there >>> are cameras and sensors that have more headroom in the bright areas. >> >> There is no way of extending the range beyond the point where all bits >> are set to "1". Not with Pentax nor with any other manufacturer. >> >> All you can do as a manufacturer is set the camera in a way that it >> deliberately 'under'exposes a little and hope that the shadows won't be >> drowned in noise. >> >> Now, if other manufacturers could hold back a little more on exposure, >> this is mainly due to the fact that they haven't been using this rotten >> Samsung sensor we have been plagued with for two camera generations. >> >> Ralf >> > > > -- > PDML Pentax-Discuss Mail List > [email protected] > http://pdml.net/mailman/listinfo/pdml_pdml.net > to UNSUBSCRIBE from the PDML, please visit the link directly above and > follow the directions. > -- M. Adam Maas http://www.mawz.ca Explorations of the City Around Us. -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net to UNSUBSCRIBE from the PDML, please visit the link directly above and follow the directions.
