On Mar 7, 2007, at 12:15 PM, Peter Lacus wrote: > Bill, > >> DSLR cameras are showing 10 stops or more of dynamic range, which >> is about 3 >> stops more than that of print film, probably 5 stops more range >> than slide >> film. > > IMHO there's only one definitive truth - film emulsions react to the > light in a different way than linear digital sensors. Indeed it's much > easier to extract useful data from digital RAW files but does it prove > that digital sensor captures wider dynamic range? IMHO it proves that > current scanners are not capable of extracting data from the film more > than anything else.
Even Kodak said there's not much usable IMAGE data in film much past the 6000-8000 ppi scanning capability of todays high-end drum scanners, Peter. There's more noise and grain data, of course, if that's what you want to extract. Drum scanners of this order can obtain more than 16 stops of useful tonal range data, if it were there. It isn't. I'm in the process of doing a K10D dynamic range measurement analysis, similar to what I did with the *ist DS a year or more back. First order look at the results seems to show that at maximum it nets 11.5 stops of DR in RAW capture mode, but whether there's anything useful about that last stop and a half is debatable. I never saw anything useful beyond about 9 stops out of B&W film with even the most exotic processing chemistry and technique, most of the time 6-7 stops was about the useful limit for negatives. Godfrey -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
