OK ... sounds convincing ;-)) Shel
> [Original Message] > From: J. C. O'Connell <[EMAIL PROTECTED]> > This isnt that complicated. Digital sensors > have dynamic range just like film does. At some point > they clip at higher light levels and at some point they just produce > noise at > lower light levels. THAT is the dynamic range of the sensor > itself and it doesn't matter what the bit depth of the A/D > is after the sensor, you cannot get more Dynamic Range in the output > than the sensor itself has by increasing the bit depth. > > That said, if the bit depth is too little compared to > the dynamic range of the sensor there will be problems > because without enough output shades of gray (bit depth) there > would be obvious visable banding as the sensor's dynamic > range increases due to technical improvements. But you have to remember > that increasing the bit depth of the output isnt > increasing the dynamic range of the sensor, it is only > making whatever dynamic range the sensor has fully usable. > > I do not claim to be an expert on this but my understanding > on this is that the sensors are limiting dynamic range at > this point, not the bit depth of the a/d conversions so just > increasing bit depths of todays sensors will not increase > the recorded dynamic range, just more more invisibly finer shades of > gray possible out of the same limited recorded dynamic > range. > > JCO > > > > > -----Original Message----- > From: Shel Belinkoff [mailto:[EMAIL PROTECTED] > Sent: Friday, November 05, 2004 1:47 AM > To: [EMAIL PROTECTED] > Subject: RE: USAF target and resolution tests > > > Greater bit depth provides greater dynamic range. That was discussed > here a week or so past, and that's what I understood from the likes of > John Francis and others, whose opinions and technical expertise I have > come to trust Anyway, all the technical talk gives me a headache. > Amplitude shmaplitude (to paraphrase another thread), I'm only > reporting what I've seen and what I've come to understand from those, > both on and off this list, who are true experts when it comes to working > with digital files. > Like I said, I'm mostly ignorant about these things, and maybe my > terminology is sometimes incorrect, but I stand by my statement, > qualifiers and all. So, if you want to argue your point on technical > grounds and theory, I'm outta here, because I just don't know enough of > the terminology and will get lost very easily. I just know what I've > seen and what the experts have shown and told me. > > Shel > > > > [Original Message] > > From: J. C. O'Connell <[EMAIL PROTECTED]> > > To: <[EMAIL PROTECTED]> > > Date: 11/4/2004 10:29:16 PM > > Subject: RE: USAF target and resolution tests > > > > I think you might have misunderstanding of what higher bit > > depth means. > > > > Bit depth is a amplitude resolution parameter, not > > a dynamic range parameter. Dynamic range of a digital sensor is > > independent of the bit depth of the output. More bits does not mean > > more dynamic range, it just means more gray shades. > > > > Bit depth is the number of grey shades from **output** pure black > > to **output** pure white, dynamic range on the other hand is the > number > > of **input** fstops between the > > sensor's pure white (clipping)output and the sensor's dark > noise(pure > > black) output . Two different digital > > sensors can have same bit depth but different dynamic range > > or vice versa.... > > > > What I was referring to about specialized films is that super low > > contrast films could have a greater DYNAMIC RANGE than digital for > > extremely contrasty scenes and super high contrast films could have a > > better amplitude resolution (bit depth) for extremely low contrast > > scenes than digital. > > > > > > JCO > > > > -----Original Message----- > > From: Shel Belinkoff [mailto:[EMAIL PROTECTED] > > Sent: Friday, November 05, 2004 12:58 AM > > To: [EMAIL PROTECTED] > > Subject: RE: USAF target and resolution tests > > > > > > I'm saying that, from what I've seen of high bit RAW files, yes, I > > believe they can. Again, take my comments with a grain of salt (and > > note the > > qualifiers) as I'm still just learning this stuff, and have just > > started to work with digi RAW files. Remember, digital can be very > > well matched with the scene, and there's control for manipulation > > throughout the workflow. > >
