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[filmscanners] Re: Colour management on Negatives
>I hate to keep rehashing this. I may be just a matter of language; but on
>the other hand, it may be a substancive matter.
I will disagree Laurie with your post but I will do it point by point.
>Therefore that would give me a profile to use in Photoshop for Fuji Superia
>200 and that specific Minolta dimage scan elite 5400.
I still stand by this.
>It will not give you a profile to use in Photoshop for the film; it will
>give you a standardized target to use as the basis for correction.
No Sir. I will recieve a negative, I will scan it. I have the measured
values of the target.
Profile Prisim will analyse the scan against the measured values and produce
a lookup table. A profile is nothing more than file that says if you measure
223 124 211 change it to 225 123 208 etc. As we all know colours are just
numbers to a computer or a printer.
I remain skeptical of the results due to the lighting of the target being at
one colour tempreture and the pictures all being taken at some other colour
tempreture.
> What the lady will be photographing is a target not a profile ( a color
profile - for
> purposes of color management - is a data file that contains a
> characterization of the color space it is characterizing).
Agreed she will give me a negative which is a film rendering of the target
>you scan furnishes a film based rendering of that target; and the file that
>you export to Photoshop will be an image file containing data about the
>captured target file image which will enable it to be reconstituted
>digitally in digital applications or by digital devices.
We do not disagree there!
> It is very possible that the exported scanner file may be tagged with a
device color
>profile that characterizes the color space that the scanner works in or
some
>standardized color profile such as sRGB as opposed to exporting a file of
>raw color values alone.
The Minolta software gives the option not to tag or to put a number of
different tags on.
> If this is the case the color values of the
>captured image file as rendered within that profiled space will be exported
>to Photoshop, which may convert from that profile to some other working
>color space profile like Adobe RGB 1998.
Not if I tell Photoshop to leave the image non colour managed!
> But in any case the target is not the profile
I never said it was a profile, it is a scan, the work of making a profile is
done in ProfilePrism after compareing the scanner RGB numbers against the
measered numbers of the target
>nor does it provide a profile to use in Photoshop that would be
>any different from what the scanner would have exported using any image.
The work of convertion will be done in Photoshop by converting to the
profile. Therefore you are correct in saying that it does not change the
export from the scanner. If it was a transparency then an IT7 target used
with Vuescan or Silverfast would make the change in the scaning software but
we believe there is no such targets available for negatives.
Vuescan does have lookup tables for Negatives but not for Superia.
>Furthermore, the orange mask does not react differently in changing
lighting
>conditions; it reacts the same for all lighing conditions.
Your expertise here is far in advance of mine. I have read that it does. You
say it does not. I am at a loss to know who is correct!
>Different kinds of orange masks will react differently from one another;
but the same kind
>of orange mask will react the same.
As above
> The film emulsion may react differently to different lighting conditions;
but that is a separate issue from >the orange mask. Different shades of
orange masking or different colors of
>masking will interact differently with the colors defined on the color film
>in negative such as to effect the positive rendering of those colors when
>reversed since you would no longer be dealing with the reversal of pure
>colors but with the reversal of colors contaminated by the mask's color.
It seems to me you are argueing that it is a mugs game to try to colour
manage negative film and that it would be preferable to use transparrency
file as there is a reasonable chance of colour managing that type of film.
That is what I'm tending to think. This morning as a present for my friend
orderd this week some 24 rolls of Fuji Superia arrived so that she has a
good supply of film. I was thinking of trying to convice her to use Velvia
100. Maybe next year!!!!!!!
Eddie
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