Bug with overprinting in Mark II/IV?

Bug with overprinting in Mark II/IV?

[Oliver Heins]

Hello,

with color black overprinting is not working.  You can easily spot this
when you use the »Ausgabevorschau« (sorry, my acrobat is in german
locale, must be something with »preview« in english; located in the
»tools« menu) in acrobat and remove magenta and black from the preview.
Whilst under the region with the magenta colored text the picture gets
shown, in the region with the black colored text the text is cut out of
the picture, leaving white.

I think this is a bug, as overprinting makes most sense with black.  It
happens both in Mark II and IV -- you have to manually copy the
hacker.jpg to your working directory (under linux e.g. with cp
$(kpsewhich hacker.jpg) /path/to/your/working/directory) and change the
path to make the minimal example work under mark iv.

Best regards,
 olli

\setupcolors[state=start,cmyk=yes,rgb=no]

\definelayer	[mybg]
		[x=0mm, y=0mm,
		width=\paperwidth, height=\paperheight,
                repeat=yes]
\setlayer	[mybg]
		[hoffset=5cm, voffset=7cm]
		{\externalfigure[sample/hacker.jpg][max]} % mark ii
%		{\externalfigure[hacker.jpg][max]} % mark iv
\setupbackgrounds[page][background=mybg]

\starttext

{\bf With foregroundcolor = magenta.}
\color[magenta]

\startoverprint
\input tufte
\stopoverprint

\color[black]
{\bf With foregroundcolor = black. \color[magenta](Some magenta
  without overprint)}
\color[black]

\startoverprint
\input tufte
\stopoverprint

\stoptext

-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
http://scriptorium-adp.de/     2544 0F07 B675 9A00 D827
1024D/9A00D827 2004-09-24 -- gpg --recv-keys 0x9A00D827
Please avoid sending me Word or PowerPoint attachments:
http://www.gnu.org/philosophy/no-word-attachments.html
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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Peter Rolf]

Oliver Heins schrieb:
> Hello,
>
> with color black overprinting is not working.  You can easily spot this
> when you use the »Ausgabevorschau« (sorry, my acrobat is in german
> locale, must be something with »preview« in english; located in the
> »tools« menu) in acrobat and remove magenta and black from the preview.
> Whilst under the region with the magenta colored text the picture gets
> shown, in the region with the black colored text the text is cut out of
> the picture, leaving white.
>
>   
I think the visible 'knockedout' text on the picture is just another 
acrobat bug. I manually checked the text and the OVP attributes are 
correctly set. If you use the coloring mechanism (Ausgabenvorschau -> 
Farbwarnungen -> [x] Überdruck anzeigen), you will see that everything 
looks ok.

> I think this is a bug, as overprinting makes most sense with black.  It
> happens both in Mark II and IV -- you have to manually copy the
> hacker.jpg to your working directory (under linux e.g. with cp
> $(kpsewhich hacker.jpg) /path/to/your/working/directory) and change the
> path to make the minimal example work under mark iv.
>
>   
I noticed this too (no picture with mkiv). BOF = Bug Or Feature :)

> Best regards,
>  olli
>
> \setupcolors[state=start,cmyk=yes,rgb=no]
>
> \definelayer	[mybg]
> 		[x=0mm, y=0mm,
> 		width=\paperwidth, height=\paperheight,
>                 repeat=yes]
> \setlayer	[mybg]
> 		[hoffset=5cm, voffset=7cm]
> 		{\externalfigure[sample/hacker.jpg][max]} % mark ii
> %		{\externalfigure[hacker.jpg][max]} % mark iv
> \setupbackgrounds[page][background=mybg]
>
> \starttext
>
> {\bf With foregroundcolor = magenta.}
> \color[magenta]
>
> \startoverprint
> \input tufte
> \stopoverprint
>
> \color[black]
> {\bf With foregroundcolor = black. \color[magenta](Some magenta
>   without overprint)}
> \color[black]
>
> \startoverprint
> \input tufte
> \stopoverprint
>
> \stoptext
>
>   

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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Taco Hoekwater]

Peter Rolf wrote:
   you have to manually copy the
>> hacker.jpg to your working directory (under linux e.g. with cp
>> $(kpsewhich hacker.jpg) /path/to/your/working/directory) and change the
>> path to make the minimal example work under mark iv.
>>   
> I noticed this too (no picture with mkiv). BOF = Bug Or Feature :)

\setupexternalfigures[location={local,global,default}]

The default value of \setupexternalfigures is {local,global}
and that does not actually search in the global texmf trees.

Best wishes,
Taco
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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[luigi scarso]

On Fri, Dec 11, 2009 at 1:53 PM, Oliver Heins <olli@sopos.org> wrote:
> Hello,
>
> with color black overprinting is not working.  You can easily spot this
> when you use the »Ausgabevorschau« (sorry, my acrobat is in german
> locale, must be something with »preview« in english; located in the
> »tools« menu) in acrobat and remove magenta and black from the preview.
> Whilst under the region with the magenta colored text the picture gets
> shown, in the region with the black colored text the text is cut out of
> the picture, leaving white.
>
> I think this is a bug, as overprinting makes most sense with black.  It
> happens both in Mark II and IV -- you have to manually copy the
> hacker.jpg to your working directory (under linux e.g. with cp
> $(kpsewhich hacker.jpg) /path/to/your/working/directory) and change the
> path to make the minimal example work under mark iv.
>
> Best regards,
>  olli
>
> \setupcolors[state=start,cmyk=yes,rgb=no]
>
> \definelayer    [mybg]
>                [x=0mm, y=0mm,
>                width=\paperwidth, height=\paperheight,
>                repeat=yes]
> \setlayer       [mybg]
>                [hoffset=5cm, voffset=7cm]
>                {\externalfigure[sample/hacker.jpg][max]} % mark ii
> %               {\externalfigure[hacker.jpg][max]} % mark iv
> \setupbackgrounds[page][background=mybg]
>
> \starttext
>
> {\bf With foregroundcolor = magenta.}
> \color[magenta]
>
> \startoverprint
> \input tufte
> \stopoverprint
>
> \color[black]
> {\bf With foregroundcolor = black. \color[magenta](Some magenta
>  without overprint)}
> \color[black]
>
> \startoverprint
> \input tufte
> \stopoverprint
>
> \stoptext
>
> --
hm I believed  was

\color[red]{......}

and
\startcolor[red]
...
\stopcolor

see
http://wiki.contextgarden.net/Colors

-- 
luigi
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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Peter Rolf]

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Taco Hoekwater schrieb:
> Peter Rolf wrote:
>    you have to manually copy the
>   
>>> hacker.jpg to your working directory (under linux e.g. with cp
>>> $(kpsewhich hacker.jpg) /path/to/your/working/directory) and change the
>>> path to make the minimal example work under mark iv.
>>>   
>>>       
>> I noticed this too (no picture with mkiv). BOF = Bug Or Feature :)
>>     
>
>   
Multiple choice:

[ ] Bug
[x] Feature
[x] The problem sits right before the monitor...

Thanks Taco!

> \setupexternalfigures[location={local,global,default}]
>
> The default value of \setupexternalfigures is {local,global}
> and that does not actually search in the global texmf trees.
>
> Best wishes,
> Taco
> ___________________________________________________________________________________
> If your question is of interest to others as well, please add an entry to the Wiki!
>
> maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
> webpage  : http://www.pragma-ade.nl / http://tex.aanhet.net
> archive  : http://foundry.supelec.fr/projects/contextrev/
> wiki     : http://contextgarden.net
> ___________________________________________________________________________________
>
>   


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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Oliver Heins]

Hi Peter,

Peter Rolf <indiego@gmx.net> writes:

> Oliver Heins schrieb:
>> Hello,
>>
>> with color black overprinting is not working.  You can easily spot this
>> when you use the »Ausgabevorschau« (sorry, my acrobat is in german
>> locale, must be something with »preview« in english; located in the
>> »tools« menu) in acrobat and remove magenta and black from the preview.
>> Whilst under the region with the magenta colored text the picture gets
>> shown, in the region with the black colored text the text is cut out of
>> the picture, leaving white.
>>
>>   
> I think the visible 'knockedout' text on the picture is just another
> acrobat bug. I manually checked the text and the OVP attributes are
> correctly set. If you use the coloring mechanism (Ausgabenvorschau -> 
> Farbwarnungen -> [x] Überdruck anzeigen), you will see that everything
> looks ok.

Yes, I noticed that, too.  But to me it looks like it is first knocked
out in the pdf, and then the overprint flag is set.

I made a document with scribus, which looks alright in acrobats preview:
http://www.sopos.org/olli/overprinting-scribus.pdf

So I doubt that this is a bug in acrobat, but in context or even in
pdftex/luatex.

>> you have to manually copy the hacker.jpg to your working directory
>> (under linux e.g. with cp $(kpsewhich hacker.jpg)
>> /path/to/your/working/directory) and change the path to make the
>> minimal example work under mark iv.
>
> I noticed this too (no picture with mkiv). BOF = Bug Or Feature :)

Feature, as Taco kindly pointed out :-)

Regards,
 olli

-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
http://scriptorium-adp.de/     2544 0F07 B675 9A00 D827
1024D/9A00D827 2004-09-24 -- gpg --recv-keys 0x9A00D827
Please avoid sending me Word or PowerPoint attachments:
http://www.gnu.org/philosophy/no-word-attachments.html
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Oliver Heins]

Hi Luigi,

luigi scarso <luigi.scarso@gmail.com> writes:

> hm I believed  was
>
> \color[red]{......}
>
> and
> \startcolor[red]
> ...
> \stopcolor

You're right, I mixed things up here.  But nontheless, my example was
(unintendedly) syntactically correct, because either \color[black]{\bf
...} and \color[black]\startoverprint ... \stopoverprint define a
block. :-)

> see
> http://wiki.contextgarden.net/Colors

Anyway, thanks for pointing it out, because I really did not know of the
\startcolor-syntax (I'm new to context).

Regards,
 olli


-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
http://scriptorium-adp.de/     2544 0F07 B675 9A00 D827
1024D/9A00D827 2004-09-24 -- gpg --recv-keys 0x9A00D827
Please avoid sending me Word or PowerPoint attachments:
http://www.gnu.org/philosophy/no-word-attachments.html
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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archive  : http://foundry.supelec.fr/projects/contextrev/
wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[luigi scarso]

On Fri, Dec 11, 2009 at 5:37 PM, Oliver Heins <olli@sopos.org> wrote:
> Hi Luigi,
>
> luigi scarso <luigi.scarso@gmail.com> writes:
>
>> hm I believed  was
>>
>> \color[red]{......}
>>
>> and
>> \startcolor[red]
>> ...
>> \stopcolor
>
> You're right, I mixed things up here.  But nontheless, my example was
> (unintendedly) syntactically correct, because either \color[black]{\bf
> ...} and \color[black]\startoverprint ... \stopoverprint define a
> block. :-)
ok, just to be sure : can you rewrite in a correct way ?
Can be a problem with mkii .

-- 
luigi
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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Oliver Heins]

luigi scarso <luigi.scarso@gmail.com> writes:

> On Fri, Dec 11, 2009 at 5:37 PM, Oliver Heins <olli@sopos.org> wrote:
>> Hi Luigi,
>>
>> luigi scarso <luigi.scarso@gmail.com> writes:
>>
>>> hm I believed  was
>>>
>>> \color[red]{......}
>>>
>>> and
>>> \startcolor[red]
>>> ...
>>> \stopcolor
>>
>> You're right, I mixed things up here.  But nontheless, my example was
>> (unintendedly) syntactically correct, because either \color[black]{\bf
>> ...} and \color[black]\startoverprint ... \stopoverprint define a
>> block. :-)
> ok, just to be sure : can you rewrite in a correct way ?
> Can be a problem with mkii .

Okay.  But I don't see any difference.

Regards,
 olli

\setupcolors[state=start,cmyk=yes,rgb=no]

\definelayer	[mybg]
		[x=0mm, y=0mm,
		width=\paperwidth, height=\paperheight,
                repeat=yes]
\setlayer	[mybg]
		[hoffset=5cm, voffset=7cm]
		{\externalfigure[sample/hacker.jpg][max]}
%		{\externalfigure[hacker.jpg][max]}
\setupbackgrounds[page][background=mybg]

\starttext

{\bf With foregroundcolor = magenta.}

\startcolor[magenta]
\startoverprint
\input tufte
\stopoverprint
\stopcolor

{\bf With foregroundcolor = black. \color[magenta]{(Some magenta
  without overprint)}}

\startcolor[black]
\startoverprint
\input tufte
\stopoverprint
\stopcolor

\stoptext


-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
http://scriptorium-adp.de/     2544 0F07 B675 9A00 D827
1024D/9A00D827 2004-09-24 -- gpg --recv-keys 0x9A00D827
Please avoid sending me Word or PowerPoint attachments:
http://www.gnu.org/philosophy/no-word-attachments.html
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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wiki     : http://contextgarden.net
___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Hans Hagen]

luigi scarso wrote:
> On Fri, Dec 11, 2009 at 5:37 PM, Oliver Heins <olli@sopos.org> wrote:
>> Hi Luigi,
>>
>> luigi scarso <luigi.scarso@gmail.com> writes:
>>
>>> hm I believed  was
>>>
>>> \color[red]{......}
>>>
>>> and
>>> \startcolor[red]
>>> ...
>>> \stopcolor
>> You're right, I mixed things up here.  But nontheless, my example was
>> (unintendedly) syntactically correct, because either \color[black]{\bf
>> ...} and \color[black]\startoverprint ... \stopoverprint define a
>> block. :-)
> ok, just to be sure : can you rewrite in a correct way ?
> Can be a problem with mkii .

overprint and similar features will not change in mkii

Hans

-----------------------------------------------------------------
                                           Hans Hagen | PRAGMA ADE
               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
      tel: 038 477 53 69 | fax: 038 477 53 74 | www.pragma-ade.com
                                              | www.pragma-pod.nl
-----------------------------------------------------------------
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Peter Rolf]

[-- Attachment #1.1: Type: text/plain, Size: 2339 bytes --]

Oliver Heins schrieb:
> Hi Peter,
>
> Peter Rolf <indiego@gmx.net> writes:
>
>   
>> Oliver Heins schrieb:
>>     
>>> Hello,
>>>
>>> with color black overprinting is not working.  You can easily spot this
>>> when you use the »Ausgabevorschau« (sorry, my acrobat is in german
>>> locale, must be something with »preview« in english; located in the
>>> »tools« menu) in acrobat and remove magenta and black from the preview.
>>> Whilst under the region with the magenta colored text the picture gets
>>> shown, in the region with the black colored text the text is cut out of
>>> the picture, leaving white.
>>>
>>>   
>>>       
>> I think the visible 'knockedout' text on the picture is just another
>> acrobat bug. I manually checked the text and the OVP attributes are
>> correctly set. If you use the coloring mechanism (Ausgabenvorschau -> 
>> Farbwarnungen -> [x] Überdruck anzeigen), you will see that everything
>> looks ok.
>>     
>
> Yes, I noticed that, too.  But to me it looks like it is first knocked
> out in the pdf, and then the overprint flag is set.
>
>   
Good point. In that case the text must be set twice, as knockout and 
overprint can't coexist. I have looked into the uncompressed mkii PDF 
(\nopdfcompression) and I can not see any obvious flaw. The parts are 
clearly separeted by '/GSknockout gs' and '/GSoverprint gs', the black 
text is not set twice.

Just an idea: the colorspace of the picture is RGB, the text is set in 
CMYK. Maybe the mixed color spaces mess up things here.


> I made a document with scribus, which looks alright in acrobats preview:
> http://www.sopos.org/olli/overprinting-scribus.pdf
>
>   
Same here. The difference is, that the picture here is also set in CMYK. 
So this points to the 'colorspace mess' theory too ;)


> So I doubt that this is a bug in acrobat, but in context or even in
> pdftex/luatex.
>
>   
>>> you have to manually copy the hacker.jpg to your working directory
>>> (under linux e.g. with cp $(kpsewhich hacker.jpg)
>>> /path/to/your/working/directory) and change the path to make the
>>> minimal example work under mark iv.
>>>       
>> I noticed this too (no picture with mkiv). BOF = Bug Or Feature :)
>>     
>
> Feature, as Taco kindly pointed out :-)
>
> Regards,
>  olli
>
>   


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___________________________________________________________________________________
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___________________________________________________________________________________

Re: Bug with overprinting in Mark II/IV?

[Oliver Heins]

Peter Rolf <indiego@gmx.net> writes:

> Oliver Heins schrieb:
>> Yes, I noticed that, too.  But to me it looks like it is first knocked
>> out in the pdf, and then the overprint flag is set.
>>
>>   
> Good point. In that case the text must be set twice, as knockout and
> overprint can't coexist. I have looked into the uncompressed mkii PDF
> (\nopdfcompression) and I can not see any obvious flaw. The parts are
> clearly separeted by '/GSknockout gs' and '/GSoverprint gs', the black
> text is not set twice.
>
> Just an idea: the colorspace of the picture is RGB, the text is set in
> CMYK. Maybe the mixed color spaces mess up things here.

But shouldn't the same effect be seen with other colors than black then,
too?  And it only happens with black, and I think it happens even when
you do it within a cmyk-only document:

Can you test the following?  My Acrobat is on a machine without net, and
my usb stick broke within the experiments.  

Best regards,
 olli

\setupcolors[state=start, cmyk=yes, rgb=no]

\starttext

{\bfb\setstrut
\startoverprint
\framed
[background=color,backgroundcolor=magenta,
foregroundcolor=yellow,align={lohi,middle},
frame=off,width=3.5cm,height=3cm]
{overprint\\\property[knockout]{knockout}}%
\stopoverprint
\framed
[background=color,backgroundcolor=magenta,
foregroundcolor=yellow,align={lohi,middle},
frame=off,width=3.5cm,height=3cm]
{knockout\\\property[overprint]{overprint}}}%

{\bfb\setstrut
\startoverprint
\framed
[background=color,backgroundcolor=magenta,
foregroundcolor=black,align={lohi,middle},
frame=off,width=3.5cm,height=3cm]
{overprint\\\property[knockout]{knockout}}%
\stopoverprint
\framed
[background=color,backgroundcolor=magenta,
foregroundcolor=black,align={lohi,middle},
frame=off,width=3.5cm,height=3cm]
{knockout\\\property[overprint]{overprint}}}%

\stoptext


-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
http://scriptorium-adp.de/     2544 0F07 B675 9A00 D827
1024D/9A00D827 2004-09-24 -- gpg --recv-keys 0x9A00D827
Please avoid sending me Word or PowerPoint attachments:
http://www.gnu.org/philosophy/no-word-attachments.html
___________________________________________________________________________________
If your question is of interest to others as well, please add an entry to the Wiki!

maillist : ntg-context@ntg.nl / http://www.ntg.nl/mailman/listinfo/ntg-context
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Re: Bug with overprinting in Mark II/IV?

[luigi scarso]

On Fri, Dec 11, 2009 at 6:57 PM, Oliver Heins <olli@sopos.org> wrote:
> But shouldn't the same effect be seen with other colors than black then,
> too?  And it only happens with black, and I think it happens even when
> you do it within a cmyk-only document:
>
> Can you test the following?  My Acrobat is on a machine without net, and
> my usb stick broke within the experiments.
>
> Best regards,
>  olli
>
> \setupcolors[state=start, cmyk=yes, rgb=no]
>
> \starttext
>
> {\bfb\setstrut
> \startoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=yellow,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {overprint\\\property[knockout]{knockout}}%
> \stopoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=yellow,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {knockout\\\property[overprint]{overprint}}}%
>
> {\bfb\setstrut
> \startoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=black,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {overprint\\\property[knockout]{knockout}}%
> \stopoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=black,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {knockout\\\property[overprint]{overprint}}}%
>
> \stoptext
>

I have found this
http://pages.cs.wisc.edu/~ghost/doc/cvs/Use.htm#SPOT

-- 
luigi
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Re: Bug with overprinting in Mark II/IV?

[Peter Rolf]

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Oliver Heins schrieb:
> Peter Rolf <indiego@gmx.net> writes:
>
>   
>> Oliver Heins schrieb:
>>     
>>> Yes, I noticed that, too.  But to me it looks like it is first knocked
>>> out in the pdf, and then the overprint flag is set.
>>>
>>>   
>>>       
>> Good point. In that case the text must be set twice, as knockout and
>> overprint can't coexist. I have looked into the uncompressed mkii PDF
>> (\nopdfcompression) and I can not see any obvious flaw. The parts are
>> clearly separeted by '/GSknockout gs' and '/GSoverprint gs', the black
>> text is not set twice.
>>
>> Just an idea: the colorspace of the picture is RGB, the text is set in
>> CMYK. Maybe the mixed color spaces mess up things here.
>>     
>
> But shouldn't the same effect be seen with other colors than black then,
> too?  And it only happens with black, and I think it happens even when
> you do it within a cmyk-only document:
>
>   
I get the same 'kind of knockedout' text as in the other example...
but the black text is set as /DeviceGray and not /DeviceCMYK 
(k-component). You can make this visible by using
'Vorschau: Separiert' with the option 'Einblenden: Nicht-DeviceCMYK'.

I think this is just a limitation of the previewer. You can define your 
own cmyk black with \definecolor[myblack][k=1]. I bet that the 
knockedout effect will vanish with cmyk black (untested).

> Can you test the following?  My Acrobat is on a machine without net, and
> my usb stick broke within the experiments.  
>
>   
prepress mess + bad luck => *have a break and enjoy your weekend* :)

> Best regards,
>  olli
>
> \setupcolors[state=start, cmyk=yes, rgb=no]
>
> \starttext
>
> {\bfb\setstrut
> \startoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=yellow,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {overprint\\\property[knockout]{knockout}}%
> \stopoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=yellow,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {knockout\\\property[overprint]{overprint}}}%
>
> {\bfb\setstrut
> \startoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=black,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {overprint\\\property[knockout]{knockout}}%
> \stopoverprint
> \framed
> [background=color,backgroundcolor=magenta,
> foregroundcolor=black,align={lohi,middle},
> frame=off,width=3.5cm,height=3cm]
> {knockout\\\property[overprint]{overprint}}}%
>
> \stoptext
>
>
>   


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Re: Bug with overprinting in Mark II/IV?

[Oliver Heins]

Hi Peter,

Peter Rolf <indiego@gmx.net> writes:

> I get the same 'kind of knockedout' text as in the other example...
> but the black text is set as /DeviceGray and not /DeviceCMYK
> (k-component). You can make this visible by using
> 'Vorschau: Separiert' with the option 'Einblenden: Nicht-DeviceCMYK'.
>
> I think this is just a limitation of the previewer. You can define
> your own cmyk black with \definecolor[myblack][k=1]. I bet that the
> knockedout effect will vanish with cmyk black (untested).

You're right.  With k=1, the 'kind of knockedout' vanishes.  Thank you
very much, Peter!

So is it advisable to change all black to cmyk black or can I safely
rely on the DeviceGray black?

>> Can you test the following?  My Acrobat is on a machine without net, and
>> my usb stick broke within the experiments.  
>>
> prepress mess + bad luck => *have a break and enjoy your weekend* :)

Well, due to your kind help, I'm able to do so now :-)

Thanks again,
 olli

-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
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Re: Bug with overprinting in Mark II/IV?

[Martin Schröder]

2009/12/12 Oliver Heins <olli@sopos.org>:
> So is it advisable to change all black to cmyk black or can I safely
> rely on the DeviceGray black?

Use CMYK. IIRC AR preflight warns about overprinting etc. not working
with Gray.

Best
   Martin
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Re: Bug with overprinting in Mark II/IV?

[Hans Hagen]

Oliver Heins wrote:
> Hi Peter,
> 
> Peter Rolf <indiego@gmx.net> writes:
> 
>> I get the same 'kind of knockedout' text as in the other example...
>> but the black text is set as /DeviceGray and not /DeviceCMYK
>> (k-component). You can make this visible by using
>> 'Vorschau: Separiert' with the option 'Einblenden: Nicht-DeviceCMYK'.
>>
>> I think this is just a limitation of the previewer. You can define
>> your own cmyk black with \definecolor[myblack][k=1]. I bet that the
>> knockedout effect will vanish with cmyk black (untested).
> 
> You're right.  With k=1, the 'kind of knockedout' vanishes.  Thank you
> very much, Peter!
> 
> So is it advisable to change all black to cmyk black or can I safely
> rely on the DeviceGray black?

if needed i can make that an option at some point (as we already have 
more such auto conversion options)

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               Ridderstraat 27 | 8061 GH Hasselt | The Netherlands
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Re: Bug with overprinting in Mark II/IV?

[Oliver Heins]

Hi Hans,

Hans Hagen <pragma@wxs.nl> writes:

> Oliver Heins wrote:
>> So is it advisable to change all black to cmyk black or can I safely
>> rely on the DeviceGray black?
>
> if needed i can make that an option at some point (as we already have
> more such auto conversion options)

That would be great. :)

Thanks,
 olli

-- 
Oliver Heins heins@sopos.org    http://oliverheins.net/
http://blog.overheins.net/     F27A BA8C 1CFB B905 65A8
http://scriptorium-adp.de/     2544 0F07 B675 9A00 D827
1024D/9A00D827 2004-09-24 -- gpg --recv-keys 0x9A00D827
Please avoid sending me Word or PowerPoint attachments:
http://www.gnu.org/philosophy/no-word-attachments.html
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Re: Bug with overprinting in Mark II/IV?

[Peter Rolf]

Am 12.12.2009 16:41, schrieb Oliver Heins:
> Hi Peter,
>
> Peter Rolf<indiego@gmx.net>  writes:
>
>    
>> I get the same 'kind of knockedout' text as in the other example...
>> but the black text is set as /DeviceGray and not /DeviceCMYK
>> (k-component). You can make this visible by using
>> 'Vorschau: Separiert' with the option 'Einblenden: Nicht-DeviceCMYK'.
>>
>> I think this is just a limitation of the previewer. You can define
>> your own cmyk black with \definecolor[myblack][k=1]. I bet that the
>> knockedout effect will vanish with cmyk black (untested).
>>      
> You're right.  With k=1, the 'kind of knockedout' vanishes.  Thank you
> very much, Peter!
>
>    
You are welcome!

> So is it advisable to change all black to cmyk black or can I safely
> rely on the DeviceGray black?
>
>    
I donno. Best ask your printing house what they prefer in this case.

Just an additional comment about prepress. A very good and gratis pdf 
book (only in german!) about prepress basics can be found here:

http://www.cleverprinting.de/ratgeber2009.html

Simply press

"Jetzt als kostenloses PDF herunterladen"

at the end of the page to get a copy. If you like it, buy it (as it's 
also very cheap for technical literature).

Best wishes,  Peter

>>> Can you test the following?  My Acrobat is on a machine without net, and
>>> my usb stick broke within the experiments.
>>>
>>>        
>> prepress mess + bad luck =>  *have a break and enjoy your weekend* :)
>>      
> Well, due to your kind help, I'm able to do so now :-)
>
> Thanks again,
>   olli
>
>    

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