Nikon Scan in Raw mode is sRGB

[John K.]

While scanning some color reversal film with my Nikon CoolScan V (LS-50)
using NikonScan 4.0.2 under Windows XP, I noticed that when the "scanner
RGB" or when Nikon Color Management system is turned OFF, the scans are
tagged with being sRGB.

"scanner RGB" or "color management off" is supposed to deliver a RAW
scan with an extremely large gamut. In Nikon's Therory probably. But as
we all know, sRGB is the complete opposite! It delivers a narrow gamut
of colors.

I thought that the files were "just being tagged" as sRGB, but were in
fact raw RGB, contains the gamut that the sensor captured at the
scanning stage.

Therefore, I scanned a colorful Velvia frame in both "color management
off", "scanner RGB", "sRGB" and "wide gamut RBG", each time I changed
modes, I restarted NikonScan.

Fired Photoshop CS/8. For this test, I set my working space to sRGB.
Then I imported the files in Photoshop CS/8.

I got the usual embedded profile mismatch warning; I picked "use
embedded profile" in all of the files. (while my working space was set
at sRGB).

In the View menu I selected "Proof Setup to sRGB" then "Gamut Warning".
"Proof Coors" was not selected.

In all 4 scans (off, wide gamut, sRGB, scaner RGB) I cranked the color
saturation slider to the max, just to see if I'll be able to get colors
out of gamut, and a coresponding warning.

The test was interesting: I was able to receive out of sRGB gamut
warnings ONLY with the "Wide Gamut RGB" scan!!!!

As with the scans done with "Nikon color management off", "Scanner RGB"
and "sRGB", they were totally happy, no matter what, in the sRGB working
space !!!!!

This is not a scientific test in any manner, but is it suffient to
demonstrate that Nikon's Color Management is in fact a "Nikon Color
Mismanagement"? and Totally misleading. Well, I would't say totally
misleading, since the Raw Scans, are in fact tagged as sRGB. Shall we
conclude that there's a sofware bug?

I thought about switching to VueScan, BUT Digital ICE4 is not supported,
and it's defect removal algorithm doesn't comapare to ICE4. Then,
there's SilverFast and it's price!

I think, that the only way to do decent scan now is with NikonScan 4.0.2
in the "Wide Gamut RGB" or Wide Gamut RGB Compensated".

Which brings me to my following question: Is there any way to prove that
in NikonScan 4.0.2 under XP the "Wide Gamut RGB" is in fact a Wide Gamut
RGB?

 

[winhag]

Did you ever try having Photoshop 'ignore' the embedded profile to see
if in fact Nikonscan was delivering
the same data for each of your tests with merely different tags?

 

[John K.]

Did you ever try having Photoshop 'ignore' the embedded profile to see

if in fact Nikonscan was delivering
the same data for each of your tests with merely different tags?

Ignoring the initial wide or narrow colorspace would have defeated the
entire purpose of the test; it wouldn't color manage the image at all.

The purpose was to see if the [supposedly] original wide gamut scan
would fit into a narrow sRGB colorspace by deliberately cracking up the
saturation.

After your reply, I just tried the 'ignore', and repeated the tests.
They were inconclusive, since all 4 versions had different colors and
saturation levels without any reference colorspace.

I guess the only way to compare is to repeat the scans with the demo
version of SilverFast Ai and compare any gamut warnings against the
scans off NikonScan.

I'm under the impression that everything that comes out of NikonScan is
Narrow Gamut, not matter what. Definitely sRGB when the Nikon color
management is turned off, in the Windows version at least.

Is there any more scientific test that can be done, with a combination
of a Target and a Software?