Preview 4.0 does not convert PDF at > 150 DPI!!???

[s.metcalf]

I'm trying to convert a PDF image to a high-resolution image file for use in an image editor. I've tried converting said PDF using Preview however it will not export at a larger resolution than 150 DPI (no matter what image format I'm converting to). This seems to be a bug or is it a restriction in Preview??? Changing the DPI to lower than 150 DPI results in smaller image files but anything larger than 150 will result in a 150 DPI resolution. This is frustrating as some of the smaller text in the document cannot be read at this resolution. Does anyone know of a work-around for this problem? I'll submit a bug report to Apple but I'd obviously like to find a solution before a response from them!

[Marvin]

Try using Seashore instead:

http://seashore.sourceforge.net/

It won't be a bug so much as a limitation I would think.

If you more complex stuff than Seashore allows, Photoshop Elements is a good app to have around too and would let you specify whatever DPI you want:

http://www.adobe.com/products/photoshopelmac/

[s.metcalf]

Great, thanks for the tip! As for PS Elements, I'm trying to keep my computer Adobe free! :D:lol::smokey:

[aegisdesign]

Create a Quartz Filter to save it as say a 300dpi PDF-X file.

1) Open the ColorSync utility...

2) Click + and name your profile 'PDF/X 300dpi' or whatever

3) Click the down arrow

4) Click 'Add PDF Retouch Component' then 'PDF/X-3

5) set the resolution to 300 and 300

6) also set any color profile you want.


In Preview, Save As... then select PDF and your new Quartz Filter. It'll also work from other applications and from the 'Save as PDF' option in Print.

[s.metcalf]

OK So I've done that but how do I then get to a 300dpi TIFF or PNG or whatever?

[aegisdesign]

Oops, sorry, I read that the wrong way. I thought you were trying to create a 300dpi PDF.

I don't think you can specify a resolution other than via an Automator Action.

[s.metcalf]

From my limited understanding of such things, there is no need to specify a resolution for PDFs because they are a vector format and can scale ad infinum. What I wanted was to be able to export the PDF to a raster format at greater than 150 DPI in order to get a reasonable representation of the drawing for use in an image editor. The app mentioned above (Seashore) can however let me specify a DPI when opening a PDF.

Oops, sorry, I read that the wrong way. I thought you were trying to create a 300dpi PDF.

I don't think you can specify a resolution other than via an Automator Action.

[aegisdesign]

From my limited understanding of such things, there is no need to specify a resolution for PDFs because they are a vector format and can scale ad infinum.

Not really.

A PDF can contain bitmap images also and you specify a resolution in the PDF so that it knows at what resolution to output at when printed.