Compressing PDF file sizes Use Preview not Acrobat

Compressing PDF file sizes: Use Preview, not Acrobat

Questions about compressing file sizes of PDF documents occasionally 
appear in these groups.  Here are my discoveries of the day on this 
topic:

1)  If you search for "Compress" in the Help file for the Mac _Finder_, 
you will bring up, at the top of the search results, a link to the 
following notably clear and helpful information:   [You'll also bring up 
a lot of additional links which I didn't explore further.]

============================================
Compressing a PDF file

You can compress a PDF file with Preview, so it's easier to email and 
archive.

This process compresses the images in the file. The compressed images 
look the same as the originals when viewed onscreen, but may appear to 
be of lower quality when printed.

   1. Open Preview, in your Applications folder.
   2. Choose File > Open, and select the PDF file to compress.
   3. Choose File > Save, choose Reduce File Size from the Quartz Filter 
pop-up menu, and choose a name and location for the new PDF file.

You can save any document as a compressed PDF file. For more 
information, click the link below.

See also

   PDF
   Saving a document as a PDF file
============================================

2)  As an aside, however, just to confirm once more how little care and 
attention Apple actually puts into its Help files and documentation, if 
you do the same search in the Help file for _Preview itself_, you will 
NOT bring up this link, or ANY other information on file compression.  
"Compressing a PDF file" i(or anything equivalent) s NOT (so far as I 
could find) listed in the List of Topics in the Preview Help window.

3)  I had a 70 page technical presentation which occupied an excessive 
28 MB as a PDF file, presumably because of 3 or 4 excessively 
high-resolution images which I had embedded in 3 or 4 of the slides.

Running this file through the "Reduce File Size" menu command in Acrobat 
reduced it to 22 MB, which wasn't a lot of help.

Running this file through the Preview process described above, however, 
reduced this file to 2.3 MB, which is lovely.

When I viewed the Preview-compressed document, all the vector graphic 
art looked fine (as you'd expect); a couple of large color images may 
have lost a little resolution or sharpness, but still looked totally 
usable; and a couple of rather grayish gray-scale images I would say had 
noticeably lost quality, but were still fully acceptable.

4)  This is only my first try with this, but I'd say that the Preview 
approach is the way to go to compress PDF file sizes, by large amounts 
in some cases, while maintaining fully adequate screen and project 
viewing quality.  And, I'd certainly like to understand how or why it is 
that Apple can write such (sometimes) superb software -- and then so 
often supply such dismal documentation for it.

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <siegman-815FE1.12040623092008@news.stanford.edu>,
 AES <siegman@stanford.edu> wrote:

> Running this file through the "Reduce File Size" menu command in Acrobat 
> reduced it to 22 MB, which wasn't a lot of help.

What version of Acrobat?

-- 
Tom "Tom" Harrington
Independent Mac OS X developer since 2002
http://www.atomicbird.com/

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <tph-FEAD49.14231523092008@localhost>,
 Tom Harrington <tph@pcisys.no.spam.dammit.net> wrote:

> In article <siegman-815FE1.12040623092008@news.stanford.edu>,
>  AES <siegman@stanford.edu> wrote:
> 
> > Running this file through the "Reduce File Size" menu command in Acrobat 
> > reduced it to 22 MB, which wasn't a lot of help.
> 
> What version of Acrobat?

7.0 Standard

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <siegman-815FE1.12040623092008@news.stanford.edu>,
 AES <siegman@stanford.edu> wrote:

> Running this file through the "Reduce File Size" menu command in Acrobat 
> reduced it to 22 MB, which wasn't a lot of help.

Under Advanced, you have more control with PDF Optimiser

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <gbi7tb$2j5$03$1@news.t-online.com>,
 Bernd Alheit <be_9002@yahoo.de> wrote:

> dorayme wrote:
> > In article <siegman-815FE1.12040623092008@news.stanford.edu>,
> >  AES <siegman@stanford.edu> wrote:
> > 
> >> Running this file through the "Reduce File Size" menu command in Acrobat 
> >> reduced it to 22 MB, which wasn't a lot of help.
> > 
> > Under Advanced, you have more control with PDF Optimiser
> > 
> 
> PDF Optimizer isn't part of the Standard edition of Adobe Acrobat.

OK. I am no expert in which editions do what. Thanks for letting me know.

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <siegman-815FE1.12040623092008@news.stanford.edu>,
 AES <siegman@stanford.edu> wrote:

> And, I'd certainly like to understand how or why it is 
> that Apple can write such (sometimes) superb software -- and then so 
> often supply such dismal documentation for it.

Well, look at Sony and many other companies with stunning technologies 
and lousy user manuals... they simply see no commercial gain in paying 
for first class work in these areas.

But that said, I have often shown people Apple's beautifully writen  
books on earlier OSs. I have some of these and they are quite a pleasure 
to read. World is faster and more cut throat these days...

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <tacitr-79AA90.00573026092008@netnews.comcast.net>,
 tacit <tacitr@aol.com> wrote:

> you can compress your PDFs just as much 
> as Preview does, only with greater control over the results.

OP might have missed my post where I gave a menu route to do just this?

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <tacitr-79AA90.00573026092008@netnews.comcast.net>,
 tacit <tacitr@aol.com> wrote:

> That's because you don't understand how to use Acrobat.
> 
> Acrobat gives you exquisite control over exactly how much reduction you 
> want, and exactly what you are prepared to sacrifice to get it. You can, 
> if you want to, choose to reduce the resolution of images (and you can 
> set exactly how much). You can choose to change the compression type, 
> compression settings, or both, on the images. You can choose whether or 
> not to compress vector artwork. You can choose to remove color profiles, 
> or to convert RGB to CMYK.
> 
> Preview doesn't do any of that. Preview just reduces everything to 72 
> pixels per inch and cranks up the JPEG compression.
> 
> If you learn how to use Acrobat, you can compress your PDFs just as much 
> as Preview does, only with greater control over the results.

Let me try rephrasing your next to last sentence, since I think you 
meant:

   "Preview just reduces _all the JPEG and similar images_ to 72 pixels 
    per inch and cranks up the JPEG compression."

which would be about what I wanted.  I'd need some tutoring on what it 
would mean for Preview to reduce vector artwork to 72 dots per inch, 
though maybe it means that Preview applies ZIP coding to the vector art 
portions?

Examining some of my compressed PDF pages in Illustrator also shows, 
however, that in situations where I'd changed a single word within a 
text string to a different font size, or used a few Symbol characters 
within a Helvetica text string, as in

      This was a BOLD move for an <PBK> academic.

      [<PBK> = Phi Beta Kappa in Greek symbols]

after compression the text string that was formerly a single unified 
text string has been split into several strings, with the BOLD and 
<PBK> characters (but not the Helvetica text substrings) now outlined 
rather than being font characters.  Not sure how that reduces space?  
Maybe it lets the associated fonts not be embedded, if there are only a 
few such instances?

Reading the Illustrator Help message entitled

   "Applying compression and downsampling in PDF files"

is educational, but I don't find the various preference options 
described there in either the Acrobat Standard or the Illustrator 
preferences.

Compressing PDF file sizes: Use Preview, not Acrobat

Questions about compressing file sizes of PDF documents occasionally 
appear in these groups.  Here are my discoveries of the day on this 
topic:

1)  If you search for "Compress" in the Help file for the Mac _Finder_, 
you will bring up, at the top of the search results, a link to the 
following notably clear and helpful information:   [You'll also bring up 
a lot of additional links which I didn't explore further.]

============================================
Compressing a PDF file

You can compress a PDF file with Preview, so it's easier to email and 
archive.

This process compresses the images in the file. The compressed images 
look the same as the originals when viewed onscreen, but may appear to 
be of lower quality when printed.

   1. Open Preview, in your Applications folder.
   2. Choose File > Open, and select the PDF file to compress.
   3. Choose File > Save, choose Reduce File Size from the Quartz Filter 
pop-up menu, and choose a name and location for the new PDF file.

You can save any document as a compressed PDF file. For more 
information, click the link below.

See also

   PDF
   Saving a document as a PDF file
============================================

2)  As an aside, however, just to confirm once more how little care and 
attention Apple actually puts into its Help files and documentation, if 
you do the same search in the Help file for _Preview itself_, you will 
NOT bring up this link, or ANY other information on file compression.  
"Compressing a PDF file" i(or anything equivalent) s NOT (so far as I 
could find) listed in the List of Topics in the Preview Help window.

3)  I had a 70 page technical presentation which occupied an excessive 
28 MB as a PDF file, presumably because of 3 or 4 excessively 
high-resolution images which I had embedded in 3 or 4 of the slides.

Running this file through the "Reduce File Size" menu command in Acrobat 
reduced it to 22 MB, which wasn't a lot of help.

Running this file through the Preview process described above, however, 
reduced this file to 2.3 MB, which is lovely.

When I viewed the Preview-compressed document, all the vector graphic 
art looked fine (as you'd expect); a couple of large color images may 
have lost a little resolution or sharpness, but still looked totally 
usable; and a couple of rather grayish gray-scale images I would say had 
noticeably lost quality, but were still fully acceptable.

4)  This is only my first try with this, but I'd say that the Preview 
approach is the way to go to compress PDF file sizes, by large amounts 
in some cases, while maintaining fully adequate screen and project 
viewing quality.  And, I'd certainly like to understand how or why it is 
that Apple can write such (sometimes) superb software -- and then so 
often supply such dismal documentation for it.

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <siegman-815FE1.12040623092008@news.stanford.edu>,
 AES <siegman@stanford.edu> wrote:

> Running this file through the "Reduce File Size" menu command in Acrobat 
> reduced it to 22 MB, which wasn't a lot of help.

What version of Acrobat?

-- 
Tom "Tom" Harrington
Independent Mac OS X developer since 2002
http://www.atomicbird.com/

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <tph-FEAD49.14231523092008@localhost>,
 Tom Harrington <tph@pcisys.no.spam.dammit.net> wrote:

> In article <siegman-815FE1.12040623092008@news.stanford.edu>,
>  AES <siegman@stanford.edu> wrote:
> 
> > Running this file through the "Reduce File Size" menu command in Acrobat 
> > reduced it to 22 MB, which wasn't a lot of help.
> 
> What version of Acrobat?

7.0 Standard

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <siegman-815FE1.12040623092008@news.stanford.edu>,
 AES <siegman@stanford.edu> wrote:

> Running this file through the "Reduce File Size" menu command in Acrobat 
> reduced it to 22 MB, which wasn't a lot of help.

Under Advanced, you have more control with PDF Optimiser

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <gbi7tb$2j5$03$1@news.t-online.com>,
 Bernd Alheit <be_9002@yahoo.de> wrote:

> dorayme wrote:
> > In article <siegman-815FE1.12040623092008@news.stanford.edu>,
> >  AES <siegman@stanford.edu> wrote:
> > 
> >> Running this file through the "Reduce File Size" menu command in Acrobat 
> >> reduced it to 22 MB, which wasn't a lot of help.
> > 
> > Under Advanced, you have more control with PDF Optimiser
> > 
> 
> PDF Optimizer isn't part of the Standard edition of Adobe Acrobat.

OK. I am no expert in which editions do what. Thanks for letting me know.

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <siegman-815FE1.12040623092008@news.stanford.edu>,
 AES <siegman@stanford.edu> wrote:

> And, I'd certainly like to understand how or why it is 
> that Apple can write such (sometimes) superb software -- and then so 
> often supply such dismal documentation for it.

Well, look at Sony and many other companies with stunning technologies 
and lousy user manuals... they simply see no commercial gain in paying 
for first class work in these areas.

But that said, I have often shown people Apple's beautifully writen  
books on earlier OSs. I have some of these and they are quite a pleasure 
to read. World is faster and more cut throat these days...

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <tacitr-79AA90.00573026092008@netnews.comcast.net>,
 tacit <tacitr@aol.com> wrote:

> you can compress your PDFs just as much 
> as Preview does, only with greater control over the results.

OP might have missed my post where I gave a menu route to do just this?

-- 
dorayme

Re: Compressing PDF file sizes: Use Preview, not Acrobat

In article <tacitr-79AA90.00573026092008@netnews.comcast.net>,
 tacit <tacitr@aol.com> wrote:

> That's because you don't understand how to use Acrobat.
> 
> Acrobat gives you exquisite control over exactly how much reduction you 
> want, and exactly what you are prepared to sacrifice to get it. You can, 
> if you want to, choose to reduce the resolution of images (and you can 
> set exactly how much). You can choose to change the compression type, 
> compression settings, or both, on the images. You can choose whether or 
> not to compress vector artwork. You can choose to remove color profiles, 
> or to convert RGB to CMYK.
> 
> Preview doesn't do any of that. Preview just reduces everything to 72 
> pixels per inch and cranks up the JPEG compression.
> 
> If you learn how to use Acrobat, you can compress your PDFs just as much 
> as Preview does, only with greater control over the results.

Let me try rephrasing your next to last sentence, since I think you 
meant:

   "Preview just reduces _all the JPEG and similar images_ to 72 pixels 
    per inch and cranks up the JPEG compression."

which would be about what I wanted.  I'd need some tutoring on what it 
would mean for Preview to reduce vector artwork to 72 dots per inch, 
though maybe it means that Preview applies ZIP coding to the vector art 
portions?

Examining some of my compressed PDF pages in Illustrator also shows, 
however, that in situations where I'd changed a single word within a 
text string to a different font size, or used a few Symbol characters 
within a Helvetica text string, as in

      This was a BOLD move for an <PBK> academic.

      [<PBK> = Phi Beta Kappa in Greek symbols]

after compression the text string that was formerly a single unified 
text string has been split into several strings, with the BOLD and 
<PBK> characters (but not the Helvetica text substrings) now outlined 
rather than being font characters.  Not sure how that reduces space?  
Maybe it lets the associated fonts not be embedded, if there are only a 
few such instances?

Reading the Illustrator Help message entitled

   "Applying compression and downsampling in PDF files"

is educational, but I don't find the various preference options 
described there in either the Acrobat Standard or the Illustrator 
preferences.