I was referring to the amplitude resolution, distict levels of gray of between absolute black and pure white. JCO
-----Original Message----- From: Jostein [mailto:[EMAIL PROTECTED] Sent: Saturday, October 23, 2004 4:43 PM To: [EMAIL PROTECTED] Subject: Re: istD bit depth Um... Are you sure resolution has anything to do with this? I thought the number of bits at any given pixel describes how many distinct levels of illumination that pixel can distinguish. The extra bits of colour depth gives more exposure latitude, but does it alter the resolution? I didn't know that... bewildered, Jostein ----- Original Message ----- From: "J. C. O'Connell" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Saturday, October 23, 2004 10:23 PM Subject: RE: istD bit depth > while the scanners may output a 16bit signal that doesn't mean it is > truly resolving 16 bits. Noise could dominate well before you get down > to that level of resolution. JCO > > -----Original Message----- > From: Jostein [mailto:[EMAIL PROTECTED] > Sent: Saturday, October 23, 2004 4:14 PM > To: [EMAIL PROTECTED] > Subject: Re: istD bit depth > > > Shel, > I think what John is saying is that it takes significantly more power to > compute the four extra bits per pixel between 12 and 16. You'd need much > stronger number-crunching logic around the chip, and more RAM as well, > to make processing of the image from chip to storage medium go > reasonably quick. With a scanner you accept a much longer exposure time > per "shot" than you would with a DSLR. > > Cameras can have 14 or 16 bit depth, and a price tag to match...:-) > > Jostein > > ----- Original Message ----- > From: "Shel Belinkoff" <[EMAIL PROTECTED]> > To: <[EMAIL PROTECTED]> > Sent: Saturday, October 23, 2004 9:51 PM > Subject: Re: istD bit depth > > > > Hi John ... > > > > Couldn't forget that linear stuff since I never knew it <vbg> > > > > Don't really understand the 2D thing. Are there two rows of pixels, > one > > below the other? Nah, that can't be it? So how come the 'blad can > have a > > 16-bit sensor, and some DSLR cameras 14-bit? Is it a matter of > space > > (which is what I'm inferring from your remarks)? I heard talk of a > Nikon > > D3 with a 16-bit sensor, BTW ... > > > > Shel > > > > > > > [Original Message] > > > From: John Francis <[EMAIL PROTECTED]> > > > To: <[EMAIL PROTECTED]> > > > Date: 10/23/2004 12:42:22 PM > > > Subject: Re: istD bit depth > > > > > > Shel Belinkoff mused: > > > > > > > > The istD has a bit depth of 12. I seem to recall some DSLR with > a bit > > > > depth of 14 ... maybe. The specs on the new Hasselblad claim a > bit > > depth > > > > of 16. Why is it that so many DSLR cameras are using a bit > depth of > > 12? > > > > Is there a physical or design reason? Cost? My little Nikon > scanner > > has a > > > > bit depth of 16 ... why not a DSLR? > > > > > > > > Shel > > > > > > Don't forget that your scanner only has a single row of sensors, > not a > > > two-dimensional array, and that it only has to work at a single > speed. > > > > > > Of the two, the fact that it's only a linear sensor is more > important. > > > You can put the extra processing elements, etc., alongside the > sensor > > > without having to worry too much how much room they take up. In a > 2D > > > sensor you're trying to put another row of pixels there. > > > > >
