Re: [NTG-context] Which color model shall I use

2018-10-01 Thread Jan U. Hasecke
On 01.10.18 10:11, Henning Hraban Ramm wrote:
> If you can ensure all RGB colors are tagged with the same profiles then it 
> should work, as long as you only care about *same* colors and not 
> (CMYK-defined) *specific* colors...
> 
> Do your SVGs declare their RGB color space?

They start with:



http://www.w3.org/2000/svg;
xmlns:xlink="http://www.w3.org/1999/xlink; x="0px" y="0px"
 viewBox="0 0 170.1 170.1" style="enable-background:new 0 0 170.1
170.1;" xml:space="preserve">

.st0{fill:#99BCDB;}
.st1{fill:#FF;}
.st2{fill:#DD4901;}
.st3{fill:#327AB8;}
.st4{fill:none;}
.st5{clip-path:url(#SVGID_2_);}
.st6{clip-path:url(#SVGID_4_);}
.st7{clip-path:url(#SVGID_6_);}
.st8{clip-path:url(#SVGID_8_);}


When I pick the screen colors with GPick I see that the SVG always stay
the same.

Only my colors I define with \definecolor change in the screen
representation of the PDF file (as I expect).

> Color management *is* complicated.

FullACK

Thanks for your help.
juh

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Re: [NTG-context] Which color model shall I use

2018-10-01 Thread Henning Hraban Ramm
Am 2018-10-01 um 09:23 schrieb Jan U. Hasecke :

> On 30.09.18 17:16, Henning Hraban Ramm wrote:
> 
>> 
>> Hi juh,
>> 
>> you can define colors in several color models at once; CMYK makes most sense 
>> for professional printing.
>> 
>> e.g. \definecolor[CompanyBlue][r=0,g=0,b=1,c=1,m=1,y=0,k=0]
>> 
>> and see https://wiki.contextgarden.net/Command/setupcolors
>> (I would activate rgb or cmyk colors via modes, if you produce different 
>> media)
> 
> I don't know how to enable this via modes.

\startnotmode[print]
\setupcolors[cmyk=no,rgb=yes]
\stopnotmode

\startmode[print]
\setupcolors[cmyk=yes,rgb=no]
\stopmode

>> CMYK colors in SVG are difficult (I needed them in 2005, nowadays there’s a 
>> hardly supported standard for icc profile based colors).
>> e.g. 
>> https://stackoverflow.com/questions/3405689/svg-image-with-cmyk-colours-is-it-possible
>> https://www.w3.org/TR/SVGColor12/#icc-colors
>> 
>> Something about color profile handling in ConTeXt:
>> https://wiki.contextgarden.net/PDFX
>> 
>> Now you must decide if you want to go the PDF/X-1a route (device dependent 
>> CYMK values) or PDF/X-3 (profiled colors).
> 
> How can I test, what colors are used in the resulting PDF? Currently I
> pick the colors with a tool in Gimp to see what colors come up.

Can Gimp check the colors in the PDF? (I don’t think so.)

I know no other tool for that than Acrobat Pro, but there probably are one or 
two others; don’t know if there are *free and usable* tools to check on 
colors/profiles in PDFs...

> If I look at the colors this way the RGB values of the included svg are
> always the original values defined by the file. All other values are not
> the values I defined in the ConTeXt files.
> 
> I think this is due to the cmyk conversion of my screen.
> 
> \setupbackend[
> format=PDF/X-3,
> intent=ISO Coated v2 (ECI),
> ]
> 
> I tried with this for example.
> 
> Anyway. Wouldn't it be better to produce a RGB-PDF and let the ripper of
> the print shop do the conversion? At least I can produce a RGB-PDF where
> all colors are defined in the same manner.

If you can ensure all RGB colors are tagged with the same profiles then it 
should work, as long as you only care about *same* colors and not 
(CMYK-defined) *specific* colors...

Do your SVGs declare their RGB color space?

Color management *is* complicated.

Greetlings, Hraban
---
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http://wiki.contextgarden.net
https://www.dreiviertelhaus.de
GPG Key ID 1C9B22FD

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Re: [NTG-context] Which color model shall I use

2018-10-01 Thread Hans Hagen

On 10/1/2018 9:23 AM, Jan U. Hasecke wrote:

On 30.09.18 17:16, Henning Hraban Ramm wrote:



Hi juh,

you can define colors in several color models at once; CMYK makes most sense 
for professional printing.

e.g. \definecolor[CompanyBlue][r=0,g=0,b=1,c=1,m=1,y=0,k=0]

and see https://wiki.contextgarden.net/Command/setupcolors
(I would activate rgb or cmyk colors via modes, if you produce different media)


I don't know how to enable this via modes.


\setupcolors[cmyk=yes,rgb=no] etc


CMYK colors in SVG are difficult (I needed them in 2005, nowadays there’s a 
hardly supported standard for icc profile based colors).
e.g. 
https://stackoverflow.com/questions/3405689/svg-image-with-cmyk-colours-is-it-possible
https://www.w3.org/TR/SVGColor12/#icc-colors

Something about color profile handling in ConTeXt:
https://wiki.contextgarden.net/PDFX

Now you must decide if you want to go the PDF/X-1a route (device dependent CYMK 
values) or PDF/X-3 (profiled colors).


How can I test, what colors are used in the resulting PDF? Currently I
pick the colors with a tool in Gimp to see what colors come up.

If I look at the colors this way the RGB values of the included svg are
always the original values defined by the file. All other values are not
the values I defined in the ConTeXt files.

I think this is due to the cmyk conversion of my screen.

\setupbackend[
  format=PDF/X-3,
  intent=ISO Coated v2 (ECI),
]

I tried with this for example.

Anyway. Wouldn't it be better to produce a RGB-PDF and let the ripper of
the print shop do the conversion? At least I can produce a RGB-PDF where
all colors are defined in the same manner.
it depends ... 4 channel cmyk doesn't map entirely on 3 channel rgb and 
vise versa


Hans

-
  Hans Hagen | PRAGMA ADE
  Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
   tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
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Re: [NTG-context] Which color model shall I use

2018-10-01 Thread Jan U. Hasecke
On 30.09.18 17:16, Henning Hraban Ramm wrote:

> 
> Hi juh,
> 
> you can define colors in several color models at once; CMYK makes most sense 
> for professional printing.
> 
> e.g. \definecolor[CompanyBlue][r=0,g=0,b=1,c=1,m=1,y=0,k=0]
> 
> and see https://wiki.contextgarden.net/Command/setupcolors
> (I would activate rgb or cmyk colors via modes, if you produce different 
> media)

I don't know how to enable this via modes.

> CMYK colors in SVG are difficult (I needed them in 2005, nowadays there’s a 
> hardly supported standard for icc profile based colors).
> e.g. 
> https://stackoverflow.com/questions/3405689/svg-image-with-cmyk-colours-is-it-possible
> https://www.w3.org/TR/SVGColor12/#icc-colors
> 
> Something about color profile handling in ConTeXt:
> https://wiki.contextgarden.net/PDFX
> 
> Now you must decide if you want to go the PDF/X-1a route (device dependent 
> CYMK values) or PDF/X-3 (profiled colors).

How can I test, what colors are used in the resulting PDF? Currently I
pick the colors with a tool in Gimp to see what colors come up.

If I look at the colors this way the RGB values of the included svg are
always the original values defined by the file. All other values are not
the values I defined in the ConTeXt files.

I think this is due to the cmyk conversion of my screen.

\setupbackend[
 format=PDF/X-3,
 intent=ISO Coated v2 (ECI),
]

I tried with this for example.

Anyway. Wouldn't it be better to produce a RGB-PDF and let the ripper of
the print shop do the conversion? At least I can produce a RGB-PDF where
all colors are defined in the same manner.

juh
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Re: [NTG-context] Which color model shall I use

2018-09-30 Thread Hans Hagen

On 9/30/2018 7:22 PM, Alan Braslau wrote:

On Sun, 30 Sep 2018 19:07:24 +0200
Hans Hagen  wrote:


Luckily I never had to match corporate colors of different models in ConTeXt...

the worst are colors specs with 4 decimals based on some design made in
indesign where one has at most 256 values per channel and then some
designer looking at his display claiming to see a difference in the 3rd
decimal betweenm his sample and the one generated by tex


I have 16bit grayscale images where the full dynamic range contains very useful 
information. Of course, no display really shows this and I doubt that any 
printer would faithfully reproduce it, yet the eye can discern the difference 
using the proper media. This is now called high dynamic range imaging in 
photography... but has been used in X-ray imaging for quite some time now.


given that the average male can only see 16 shades of gray ...


For reasons of quality or transparency, rather free dissemination of 
information, it would be useful to be able to distribute a PDF including these 
images with their whole 16bit dynamic range. Of course, any or most all PDF 
readers would only display 8bits, but one could in principal extract the 
underlying image for examination and analysis.

c m y k in 16 bit would mean 4 * 8 bytes per pixel

(ok, one day we migh twant to store raw images made by these multi-ccd 
(in high end) phone camera and do all these sharp and zoom corrections 
outside that device .. interesting techniques btw)


Hans


-
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  Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
   tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
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Re: [NTG-context] Which color model shall I use

2018-09-30 Thread Alan Braslau
On Sun, 30 Sep 2018 19:07:24 +0200
Hans Hagen  wrote:

> > Luckily I never had to match corporate colors of different models in 
> > ConTeXt...  
> the worst are colors specs with 4 decimals based on some design made in 
> indesign where one has at most 256 values per channel and then some 
> designer looking at his display claiming to see a difference in the 3rd 
> decimal betweenm his sample and the one generated by tex

I have 16bit grayscale images where the full dynamic range contains very useful 
information. Of course, no display really shows this and I doubt that any 
printer would faithfully reproduce it, yet the eye can discern the difference 
using the proper media. This is now called high dynamic range imaging in 
photography... but has been used in X-ray imaging for quite some time now.

For reasons of quality or transparency, rather free dissemination of 
information, it would be useful to be able to distribute a PDF including these 
images with their whole 16bit dynamic range. Of course, any or most all PDF 
readers would only display 8bits, but one could in principal extract the 
underlying image for examination and analysis.

Just an idea.

Alan 
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Re: [NTG-context] Which color model shall I use

2018-09-30 Thread Hans Hagen

On 9/30/2018 5:16 PM, Henning Hraban Ramm wrote:


Luckily I never had to match corporate colors of different models in ConTeXt...
the worst are colors specs with 4 decimals based on some design made in 
indesign where one has at most 256 values per channel and then some 
designer looking at his display claiming to see a difference in the 3rd 
decimal betweenm his sample and the one generated by tex


-
  Hans Hagen | PRAGMA ADE
  Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
   tel: 038 477 53 69 | www.pragma-ade.nl | www.pragma-pod.nl
-
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Re: [NTG-context] Which color model shall I use

2018-09-30 Thread Hans Hagen

On 9/30/2018 3:46 PM, Jan U. Hasecke wrote:

Hi,

I would like to know, how to define colors to have a good printing quality.

I am currently producing print materials for a company where all colors
were defined for online usage first, so we started with defining RGB
colors and then derived CMYK colors.

What is the best approach for defining colors in print materials? What
color model shall I use? RGB or CMYK?

For the background. We have some SVG graphics we use on the website.
They are defined in RGB color model. And we use them in the print
materials as well.

I tend to define RGB colors in my print documents so that the colors of
the included SVG files match the defined colors I use elsewhere in the
document. Eg. the Corporate-Blue of the Logo (SVG) will match the Blue
of the headlines.

I could as well define CMYK colors in the document but then I have two
different color models in one document and I fear that the colors are
printed in different hues.

What would you do?

rgb for screen and cmyk for print

You can use rgb and in the print version enable cmyk and disable rgb in 
which case context will convert for you.


For most color setups the result is ok (the end users often don't know 
what colors were meant anyway) as long as relative coloring is ok (the 
wierder the colors, the more sensitive for colro spaces).


Hans


-
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Re: [NTG-context] Which color model shall I use

2018-09-30 Thread Henning Hraban Ramm
Am 2018-09-30 um 15:46 schrieb Jan U. Hasecke :

> Hi,
> 
> I would like to know, how to define colors to have a good printing quality.
> 
> I am currently producing print materials for a company where all colors
> were defined for online usage first, so we started with defining RGB
> colors and then derived CMYK colors.
> 
> What is the best approach for defining colors in print materials? What
> color model shall I use? RGB or CMYK?
> 
> For the background. We have some SVG graphics we use on the website.
> They are defined in RGB color model. And we use them in the print
> materials as well.
> 
> I tend to define RGB colors in my print documents so that the colors of
> the included SVG files match the defined colors I use elsewhere in the
> document. Eg. the Corporate-Blue of the Logo (SVG) will match the Blue
> of the headlines.
> 
> I could as well define CMYK colors in the document but then I have two
> different color models in one document and I fear that the colors are
> printed in different hues.
> 
> What would you do?

Hi juh,

you can define colors in several color models at once; CMYK makes most sense 
for professional printing.

e.g. \definecolor[CompanyBlue][r=0,g=0,b=1,c=1,m=1,y=0,k=0]

and see https://wiki.contextgarden.net/Command/setupcolors
(I would activate rgb or cmyk colors via modes, if you produce different media)

CMYK colors in SVG are difficult (I needed them in 2005, nowadays there’s a 
hardly supported standard for icc profile based colors).
e.g. 
https://stackoverflow.com/questions/3405689/svg-image-with-cmyk-colours-is-it-possible
https://www.w3.org/TR/SVGColor12/#icc-colors

Something about color profile handling in ConTeXt:
https://wiki.contextgarden.net/PDFX

Now you must decide if you want to go the PDF/X-1a route (device dependent CYMK 
values) or PDF/X-3 (profiled colors).

Luckily I never had to match corporate colors of different models in ConTeXt...


Greetlings, Hraban
---
https://www.fiee.net
http://wiki.contextgarden.net
https://www.dreiviertelhaus.de
GPG Key ID 1C9B22FD

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[NTG-context] Which color model shall I use

2018-09-30 Thread Jan U. Hasecke
Hi,

I would like to know, how to define colors to have a good printing quality.

I am currently producing print materials for a company where all colors
were defined for online usage first, so we started with defining RGB
colors and then derived CMYK colors.

What is the best approach for defining colors in print materials? What
color model shall I use? RGB or CMYK?

For the background. We have some SVG graphics we use on the website.
They are defined in RGB color model. And we use them in the print
materials as well.

I tend to define RGB colors in my print documents so that the colors of
the included SVG files match the defined colors I use elsewhere in the
document. Eg. the Corporate-Blue of the Logo (SVG) will match the Blue
of the headlines.

I could as well define CMYK colors in the document but then I have two
different color models in one document and I fear that the colors are
printed in different hues.

What would you do?

TIA
juh
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