Hi Godfrey I am new to this list, though not to Pentax, nor digital. In spite of this I still seem to wrestle daily with the 'right' settings and the 'best' software for interpreting RAWs. I also have a Sony R1, BTW.
Are you saying that, regardless of whether you have the camera set to JPEG or RAW, the meter readout will always be the same for the given scene BUT that using RAW really needs extra exposure, as if RAW and JPEGS were two different 'films', each having slightly different ISO ratings? I am the proud owner of a K20D (previous camera has been Minolta D7, Pentax *istDS, Sony R1) for 2 weeks. Not had much time to play yet, though I have noticed that I have already taken 400 shots with it, many being just test shots (and the cat loves to pose too). The weather here in the UK is fairly appalling at the moment and the first weekend of use it was very dull and overcast. I prefer to shoot RAW. At first, I was a little disappointed, thinking that many of the shots were up to a stop underexposed ... Even though we had even (though dull) lighting. The histograms are shifted to the left. In Lightroom the shots looked way too contrasty and muddy by default. I am also trialing Silkypix (too many variables here perhaps) and really like it. It seems to render the images better, less contrasty and perhaps brighter, by default. Looking at the shots a day or so later I thought, actually they don't seem too bad afterall. Many needed a slight push up on the exposure but not as much as I had originally thought. I got my Sony R1 out and started comparing its meter readings with the K20D for the same focal length shots, same ISO settings etc, set to RAW. (My neighbours must think I'm some sort of freak or nutter). Most of the time they were in agreement. What I did see though was that the K20D was *much* more sensitive ... Only a slight shift of the camera left or right would make it fluctuate. I wonder if the Pentaxes 'panic' if anything in the frame is considered a highlight, even on evaluative metering? For example, I only need to shift the K20D upwards slightly to include a small amount of extra sky and the meter reading changes. The Sony would need a little more of a shift. So, I am slightly confused but if it is generally true that cameras need or ought to meter differently for JPEG or RAW, then that is interesting stuff! Why can't Pentax just make the firmware change this automtically? I hope to do some more testing this weekend. Cheers Lee ------------------------------ >Message: 10 >Date: Thu, 01 May 2008 10:30:18 -0700 >From: Godfrey DiGiorgi <[EMAIL PROTECTED]> >Subject: Re: K10D v Lightroom exposure and histograms >To: Pentax-Discuss Mail List <[email protected]> >Message-ID: <[EMAIL PROTECTED]> >Content-Type: text/plain; charset=US-ASCII; delsp=yes; format=flowed > >The Pentax DSLR cameras' metering systems are calibrated to produce >accurate exposure estimation for their *default* configuration ... >JPEG capture (and in the case of the *ist DS, BRIGHT color >rendering). They don't recalibrate for RAW exposure, where accurate >exposure estimation should be greater due to RAW files' improved >headroom. > >That's why what you're seeing is JPEGs that are brighter than RAWs >when viewing RAW+JPEG capture in Lightroom, where you haven't told >Lightroom to ignore JPEG sidecars. > >With the *ist DS, I typically found that I needed to add +.3 to +.7 >EV for all RAW captures. The K10D's bias is more accurate, I'm >typically adding only up to +.3 EV for average scenes. These biases >in meter calibration are also, I feel, a reason why some people >shooting with RAW capture tend to complain about noise. > >My Sony R1 actually recalibrated the meter when I turned on RAW >capture, it adjusted the bias such that average scenes never required >EV compensation. > >Godfrey -- 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.
