Colour Gamit Issue?

Hi all,

I responded to a question on alt-graphics-photoshop that's left me puzzled
....

It concerns a lady who's composed an image in an RGB space then converted it
to CMYK (I doubt it's what she needs, but that's a different story).

I did some testing on an image I took of my kids in a forrest (lots of leafy
trees in background). I opened the image in an RGB space, and as soon as I
converted it to CMYK I lost about 1/2 the saturation in (many of) the
greens - kids clothing and skin tones were unaffected.

I've never had occasion to work in CMYK before - what's going on here? - is
this simply an out of gamut issue?

I'm having a hard time accepting that CMYK would be THAT challenged to
reproduce green leaves?

Any advice "muchly" appreciated.

Cheers,

Colin

On Mon, 23 Jan 2006 10:13:08 +1300, "C J Southern"
wrote:

Hi all,

I responded to a question on alt-graphics-photoshop that's left me puzzled
...

It concerns a lady who's composed an image in an RGB space then converted it
to CMYK (I doubt it's what she needs, but that's a different story).

You should ask her :-)

I did some testing on an image I took of my kids in a forrest (lots of leafy
trees in background). I opened the image in an RGB space, and as soon as I
converted it to CMYK I lost about 1/2 the saturation in (many of) the
greens - kids clothing and skin tones were unaffected.

I've never had occasion to work in CMYK before - what's going on here? - is
this simply an out of gamut issue?

Yes, it is. CMYK have a much smaller gamut than monitor color spaces
(sRGB, Adobe RGB etc).

I'm having a hard time accepting that CMYK would be THAT challenged to
reproduce green leaves?

Any advice "muchly" appreciated.

Very bright (sRGB) green is probalby out of CMYK gamut. There are
several ways to convert the colors to be inside the desired color
space. An easy way is to select colors outside gamut with color picker
and desaturate them.

-espen
--
http://www.seland.org/