Re: filmscanners: which space?

["Maris V. Lidaka, Sr." <mlidaka@ameritech.net>]

Firstly, if the results were as per your example I would look for a new
RGB-CMYK and/or CMYK-RGB conversion profile.  Even visually the colors are
different.

If, however, such a result should be, then the 16 points are 6% of the total
gamut which is sufficient to adjust the green - I can't fathom wanting to
change it more than that.  And I can adjust B or R as well to compensate for
the G.

The point is that yes, there will be damage and loss without question but,
at least for me, there are times when the benefits of being able to adjust
in CMYK outweigh these damages.

Maris

----- Original Message -----
From: "Karl Schulmeisters" <karlsch@earthlink.net>
To: <filmscanners@halftone.co.uk>
Sent: Saturday, May 26, 2001 3:51 PM
Subject: Re: filmscanners: which space?


| The complexity comes in when you add translation into another device.
|
| Lets say your original RGB values were 128,64,168, then after mapping
| through CYMK and back to RGB you now have 138,16, 186 (I'm making these
| numbers up, but they're somewhat believable.  Now you want to print to a
| printer that tends towards green and only takes RGB as input.  So you
print
| a test print and low and behold its too green.  You only have 16 levels of
| green left to futz with.
|
|
| From: "Maris V. Lidaka, Sr." <mlidaka@ameritech.net>
| To: <filmscanners@halftone.co.uk>
| Sent: Saturday, May 26, 2001 11:58 AM
| Subject: Re: filmscanners: which space?
|
|
| > Which is fine by me - so long as RxGxBx look the same as Rx'Gx'Bx' my
| result
| > will be what I want it to be.
| >
| > Maris
| >
| > ----- Original Message -----
| > From: "Karl Schulmeisters" <karlsch@earthlink.net>
| > To: <filmscanners@halftone.co.uk>
| > Sent: Saturday, May 26, 2001 2:23 AM
| > Subject: Re: filmscanners: which space?
| >
| >
| > | That's not exactly the case.  What is the case is that a particular
Hue,
| > | Intensity value - what our eyes perceive as a unique 'color value' can
| be
| > | rendered with multiple combinations of RGB.  The same is not true for
| CYMK
| > |
| > | So when you map from RGB into ANY color space, you essentially lose
some
| > | information.  Namely you lose the mapping back to the original value
| > | settings.  That doesn't mean you can't get back to an RGB triplet that
| > will
| > | look the same, but it does mean that say if you had set the RGB
triplet
| > | value to Rx,Gy,Bz then mapped to CYMK and you went back, Rx',Gy',Bz'
| might
| > | not have
| > | x=x',y=y',z=z'.
| >
| > [snipped]
| >
|
|
|