I have a Nikon Coolscan IV ED but haven't used it a lot yet. I bought it
because I thought that it would give me 48 bit scans, well I can only scan
at 12 bits, but the manual mentions 48 bit output, can someone explain this
to me? So far, I'm not getting the results that I was hoping for, perhaps
it's because I just haven't mastered the art of scanning. I also have an
Epson Perfection 2450 flatbed, would I be better off using the transparency
feature on it for my 35mm slides? I haven't compared the two yet. Also,
would I be better off getting software such as VueScan, will it perform
better than the software that came with my scanners?

Thanks all!
--
Ray: www.rayspace.com
"I'd rather wake up in the middle of nowhere,
than in any city on earth" - Steve McQueen

In article <vjvh6utc79d093@corp.supernews.com>, yar@easystreet.com says...

Computers use word sizes of 8, 16, or 32 bits (multiples of 8 bit bytes,
cannot really use half a byte). It is a 12 bit scanner, so 12 bit data is
necessarily stored in a 16 bit word. Three 16 bit words for the three RGB
channels is 48 bits.

The concept of 12 bits in a 16 bit word is much like the idea of putting 8
eggs into a dozen egg carton. Four compartments or bits are simply empty or
zero. This is much easier than manufacturing new egg cartons, and we would
still have 8 eggs either way.

It is possible to imagine a way to pack the data bits tighter than 12 bits
in a 16 bit word, and this packing was done in the early days of computers
when memory was very expensive. But that would make every access of the
millions of pixels be frightfully inefficient and slow... Memory is so
cheap today that it is far better to just waste the 4 bits per word for the
sake of efficiency and speed.

Many people do like VueScan, and it works with both scanners. Free trial at
www.hamrick.com, try it and see what you think.

--
Wayne
http://www.scantips.com "A few scanning tips"

"Lunaray" <yar@easystreet.com> wrote:

I suppose, the scanner has an infrared channel for ICE. That is a fourth
channel in addition to red, green and blue. So probably you have four
channels with each 12 bit, in sum 48 bit.

And Wayne is right, that these 48 bit are padded with extra bits.
The scanner sends to the computer in total 64 bits per pixel, but
only 48 will be used with real data.

No. The film scanner will be really far better, especially in dark regions
of the transparency.

Regards,
Kurt.

In article <nBC0b.816809$Vi5.18096516@news1.calgary.shaw.ca>, artistic-
1@shaw.ca says...
Yes, Photoshop sees it as a grayscale Alpha Channel. And the dust shows
up VERY nicely on it :-)



--
Mac McDougald
Doogle Digital - www.doogle.com