Convert to Grayscale

Sébastien Mengin

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Jun 21, 2009, 9:41:55 AM6/21/09

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Hi all,

I have a PDF file containing lots of images in CMYK colors.

For economic reasons, we decide to finally print in Grayscale.
But I'd like not to convert each images one by one.

Is there a simple way to convert the PDF file into Grayscale before
sending it to the printshop?

I have Adobe Acrobat 6.0 but I am not very familiar with it...

Thanks for anu tips,
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S�bastien
http://edilibre.net

Matti Vuori

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Jun 21, 2009, 10:26:02 AM6/21/09

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S�bastien Mengin <seba...@edilibre.net> wrote in
news:slrnh3se54.b...@localhost.localdomain:

> I have a PDF file containing lots of images in CMYK colors.
>
> For economic reasons, we decide to finally print in Grayscale.
> But I'd like not to convert each images one by one.

Why should you need to do this? I would guess the printshop can (in most
cases) use the CMYK version just fine.

--
Matti Vuori, <http://www.kotiposti.net/~xmvuori/index-e.htm>

Sébastien Mengin

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Jun 21, 2009, 10:42:28 AM6/21/09

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Le 21-06-2009, Matti Vuori <mvu...@koti.soon.fi> a �crit�:

> S�bastien Mengin <seba...@edilibre.net> wrote in
> news:slrnh3se54.b...@localhost.localdomain:
>> I have a PDF file containing lots of images in CMYK colors.
>>
>> For economic reasons, we decide to finally print in Grayscale.
>> But I'd like not to convert each images one by one.
>
> Why should you need to do this? I would guess the printshop can (in most
> cases) use the CMYK version just fine.

The problem is that in my case there are lots of people between me and
the printshop and it would be far more comfortable for everyone that I
provide the final PDF correctly.

Thanks for the comment anyway!

Lutrin

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Jun 21, 2009, 11:18:18 AM6/21/09

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On Sun, 21 Jun 2009 13:41:55 +0000, Sébastien Mengin ci disse:

> Is there a simple way to convert the PDF file into Grayscale before
> sending it to the printshop?

[...]
I use ghostscript (release 8.62 or higher) with this command-line options
(must be all on single line)

gs -sOutputFile=output.pdf -sDEVICE=pdfwrite -sColorConversionStrategy=Gray -dProcessColorModel=/DeviceGray -dCompatibilityLevel=1.4 input.pdf < /dev/null
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Sébastien Mengin

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Jun 22, 2009, 7:48:26 AM6/22/09

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Le 21-06-2009, Lutrin <eli...@olympo.it> a �crit�:

> I use ghostscript (release 8.62 or higher) with this command-line options
> (must be all on single line)
>
> gs -sOutputFile=output.pdf -sDEVICE=pdfwrite
> -sColorConversionStrategy=Gray -dProcessColorModel=/DeviceGray
> -dCompatibilityLevel=1.4 input.pdf < /dev/null

Thanks a lot!

It seems to work perfectly.

One last question: with such a command line, the PDF obtained has lost
approx 10 Mo (the original file was 25 Mo). Is the inital resolution of
the new PDF preserved?

Lutrin

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Jun 22, 2009, 7:53:46 AM6/22/09

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On Mon, 22 Jun 2009 11:48:26 +0000, Sébastien Mengin ci disse:

> One last question: with such a command line, the PDF obtained has lost
> approx 10 Mo (the original file was 25 Mo). Is the inital resolution of
> the new PDF preserved?

[...]
the answer is: yes: pdf has decreased its size due to conversion from cmyk
to grayscale (resolution stills untouched), I use usually this method to
printing in offset with only black plate (able to print also grayscale)

Sébastien Mengin

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Jun 22, 2009, 8:01:49 AM6/22/09

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Le 22-06-2009, Lutrin <eli...@olympo.it> a �crit�:

> the answer is: yes: pdf has decreased its size due to conversion from cmyk
> to grayscale (resolution stills untouched), I use usually this method to
> printing in offset with only black plate (able to print also grayscale)

All right. Thanks again.