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. > >
