I believe that more headroom in the dark areas is in the nature of the sensor wells.
When a cup is full, you can't pour more water into it. If you try to, you pours over. I think it is almost as simple as that. In the dark areas, on the other hand, the information will be obscured by noise, but it the information is present. In other words, you can recover more information there. Higher dynamic range gives us opportunity to expose more conservatively without loosing information. I think this is what gives us more headroom in practical use. But as suggested; I'm just a bloke who speculates on this topic. Others may have mush better answers. -- MaritimTim http://maritimtim.blogspot.com/ 2010/11/7 Boris Liberman <[email protected]>: > Tim, this is my understanding as well. However, I want to know how much of > it goes to the dark areas (see the 9.5 EV pull out from /almost/ total > blackness example) and how much of it goes to the bright areas (remains to > be seen). In particular K-7 seems to have somewhat deeper DR in dark areas > wheres in bright areas it simply sucks. Considering the fact that Pentax do > not advertise any changes in their PRIME engine, I would hazard a guess that > the bias is still similar - most of the DR goes to the dark part of the > histogram. Thus is my interest. > > Boris > > > On 11/7/2010 2:23 PM, Tim Øsleby wrote: >>> >>> From my limited understanding, the higher dynamic range of the K-5 >> >> indicates a lot more headroom. I may be totally wrong about this. >> >> -- >> MaritimTim >> >> http://maritimtim.blogspot.com/ >> >> >> >> 2010/11/7 Boris Liberman<[email protected]>: >>> >>> Funny you should post this report, Jaume. Few days ago I had very similar >>> experience with my K-7 - misconfigured the flash and it did not fire in >>> rather dimly lit room. I had to apply a bit of Topaz Denoise (but again, >>> I >>> fancy it now, 'cause it is my most recent 'toy') and the picture was >>> totally >>> salvageable. >>> >>> The opposite however is much more interesting. Off top of my head, K10D >>> has >>> about 1 Ev (may be a bit more) of RAW headroom in bright areas. K-7 in >>> turn >>> has hardly 0.5 Ev. In fact, K-7 really sucks when it comes to dealing >>> with >>> bright light - minimal exposure error - total loss. I will be much more >>> interested to know how K-5 fares in that department. I sincerely hope it >>> does better than both K10D and K-7. >>> >>> Oh yes, I just said that out loud - K-7 sensor really sucks. >>> >>> Boris >>> >>> >>> On 11/6/2010 10:47 PM, Jaume Lahuerta wrote: >>>> >>>> This fortunate Spanish K-5 owner tried to recover a picture where the >>>> flash >>>> didn't fire when it was supposed to do (it wasn't charged). >>>> >>>> >>>> They challenged the camera for fun and were surprised by the results: >>>> http://www.pentaxeros.com/forum/index.php?topic=37916.0 >>>> >>>> >>>> >>>> >>>> >>> >>> >>> -- >>> 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. >>> >> > > > -- > 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. > -- 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.
