Pages 08 PDF Export Resolution

As you probably know, there are two ways to create PDF files using Pages - print PDF or export PDF. If you choose the export option you have three quality levels with each quality determining the quality of your graphic files. Set to best, the resolution of images isn’t scaled down. Set to better, images are downsampled to 150 dpi. Set to good, images are downsampled to 72 dpi.

If you choose the Print PDF option you can either choose Open PDF in Preview - and from there you can save the PDF file compressing the images, or you can simply select print. The print option uses the default PDF profile which is, I believe, best image quality. BTW, you can create additional PDF profiles, thereby gaining more control over the export quality of images and then create automator workflows that will appear in the Print PDF menu.

I created a sample document in Pages '08 and pulled in a couple photos from Aperture and a couple from iPhoto. After saving the document, I opened the package and examined each jpeg inside. Each picture file was the size I expected, opening in Photoshop each was the expected size, each was the expected resolution. When I exported as a PDF using the best option, I saw what I expected - the PDF was about the size of the Pages document which I expected.

I forgot to mention one other point in my original post. If you use Pages to perform any formatting on a picture - if you adjust it, if you use an alpha channel, or if you use a mask, multiple copies of the picture will be kept in Pages - I assume so you can undo. But when you export all those extra copies don't go into the PDF. That might account for the difference in size.

In short, I'm not seeing pictures losing rez or size when I export the PDF.

10 M files sound like RAW formats of some kind. I do not know if PDF officially supports RAW, so Pages may convert them to JPEG or something.

It is also possible that what you import from Aperture is a jpeg preview version of the raw file. Perhaps there is a setting in Aperture to change this.

In general, if you intend to print on a digital press or offset lithographic press, you should be using the PDF/X-3 export path in order to prepare a printing master as per the ISO rendering specification. You should use the OutputIntent for the intended printing condition which is almost always much, much higher gamut than the Generic CMYK Profile that Apple sets as default. This is a not very good separation for very, very low gamut US magazine printing on grayish paper. If you separate for such a small gamut, you are loosing colours that could be printed in higher gamut conditions e.g. on art paper in ISO 12647 see www.color.org and www.eci.org which also has default OutputIntent profiles.

If you are using a PDF/X-3 process, there are also PDF/X-3 validation tools, including those in Acrobat Professional. They will warn you if the resolution is too low for the default frequency you need (aka 'screening' although the term is defunct as nobody uses glass plates with lines in them these days -:)).

Best,

hh

The Help is clear:

PDF: PDF files can be created using an image quality of good, better, or best.
_When the image quality is set to best, the resolution of images isn’t scaled down._
When the image quality is set to better, images are downsampled to 150 dpi.
When the image quality is set to good, images are downsampled to 72 dpi.
Images without an alpha channel are JPEG compressed with a compression level of 0.7 at the good setting and 0.9 at the better setting.

If I understand well, this means that if we use the best quality and if the original picture is a 600 dpi one, it will remain at 600 dpi.

Yvan KOENIG (from FRANCE jeudi 10 juillet 2008 21:29:34)

The "page" does not really have a dpi, but each individual image does. To me all the original pixels are visible.

What is imported from Aperture is not the image itself, but a preview of it. To set the quality and size of the preview go to Aperture's preferences > Previews. As you already have previews, you will have to regenerate them. To do this, hold down the "alt" key and go to the menu Images > Generate Previews.

What is imported from Aperture is not the image itself, but a preview of it.

Ouch - As far as I know Aperture, like LinoColor, Live Picture and Xres, has proxies or previews. These contain the commands for colour correction in a low resolution rendering. The final form rendering for high resolution is accomplished at run time, so the colour correction is non-destructive. You never ever need to destroy your digital original. If what is placed in Pages is not a final form rendering, then it seems a recipe for process problems. What happens if the Pages document is moved from one Mac to another Mac and the preview is then then only rendering on the local system?

hh

Henrik Holmegaard wrote:

What is imported from Aperture is not the image itself, but a preview of it.

Ouch - As far as I know Aperture, like LinoColor, Live Picture and Xres, has proxies or previews. These contain the commands for colour correction in a low resolution rendering. The final form rendering for high resolution is accomplished at run time, so the colour correction is non-destructive. You never ever need to destroy your digital original. If what is placed in Pages is not a final form rendering, then it seems a recipe for process problems. What happens if the Pages document is moved from one Mac to another Mac and the preview is then then only rendering on the local system?

Good point. But as long as the preview contains a colour profile, it should be possible to handle, shouldn't it?

Anyhow, I find it annoying that you do not get the master by default. It is rather cumbersome to have to change preview settings to get the quality you expect. I can see the development and logical constraints - the user may have the master on a drive that is not even connected. However, the behaviour clearly causes confusion for the users.

But as long as the preview contains a colour profile, it should be possible to handle, shouldn't it?

The ICC profile for the calibrated state of the camera and the ICC profile for the calibrated state of the colour display set up the minimum colour world for the colour correction.

To preview the colour correction in the context of a sample printing condition, a third colour profile must be included in the colour world.

But the dicey bit here is not whether the preview includes the ICC profile for the source, that is, for the camera.

The dicey bit is whether the right resolution and right crop per the colour proxy for preview gets into the final form rendering when the PDF is built.

If it is possible to blur the boundary between colour proxy for preview and final form rendering, then it is presubably preferable to deliberately do a final form rendering and place that in Pages.

Best

hh