Jostein wrote:
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...
Resolution of color space,
-Ryan
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.
