Preparing Large (Oversized) PDFs from Illustrator Documents for Printing

[Shennoz]

Hello everyone,

I'm a novice when it comes to printing and I need some advice, please.

I've been asked to design a 2.5x8 metres banner. Because of Illustrator document size limits I created it half the size of the final print (1.25m x 4m), but now I ran into another issue: The print shop wants me to send them the design in PDF format, but when I print to PDF it doesn't allow me to create a document 4 metres wide! When printing into PDF my available options are "doPDF v7" & "Adobe PDF". Both allow maximum width/height at approximately 2.7 metres.

I am now left with 3 options:

1. Print to PDF in even smaller size (0.625m x 2m) and let the print shop scale it up 4 times on the printer to get the required print size (2.5x8).
2. Split the artboard (and hence design) into two, each at 1.25x2 metres, and let the print shop scale it 2 times, then print and attach the two parts together.
3. Create 4 artboards, each 2.5x2 metres and split the design into 4 parts per artboard, which can be printed & combined together into the final 2.5x8 banner with no scaling required.

Which is the proper workflow to achieve this? Or is there an entirely different method?

Thanks.

[Jacob Bugge · Accepted solution]

Shennoz,

A PDF can always be resized, so 1. is the obvious choice.

Just make sure that the AI document/file is made with the right/sufficient resolution for possible raster effects and raster images.

The size (in pixels x pixels) in raster images should correspond to the desired resolution at the full/final size (2.5x8 m), and the resolution of raster effects (Effect>Raster Effects Settings) should be twice the desired value at the full/final size (2.5x8 m).

Obviously, the desired/needed resolution depends on the intended viewing distance, you may ask the printing shop.

[Shennoz]

Thank you Jacob! I was leaning towards option 1 myself but needed the confirmation that PDFs can scale freely with vector art.

I understand what you meant about raster image resolution corresponding to the final size. However, could you please elaborate on why raster effects' resolution should be twice & and not equal to the value at the full/final size? Are raster effects more lossy than raster images?

[Jacob Bugge]

Shennoz,

Are raster effects more lossy than raster images?

No, but they have the specific resolution chosen under Effect which means that they have a specific number of steps, corresponding to a specific pixel x pixel size for images.

Therefore, when you create the artwork at the size 1.25m x 4m, the chosen resolution under Effect applies to that size and is reversely scaled when you change the size.

When you save/print it at the size 0.625m x 2m as PDF, the original resolution will be doubled.

When it is printed at the final size 2.5m x 8m, the original resolution will be halved, and therefore the raster effects resolution should be twice the value at the full/final size.

By the way I failed to notice that you print to PDF.

if you Save As PDF, or preferably Save a Copy as PDF (to avoid the risk of losing your original AI document/file) rather than print to PDF you have control of the PDF properties.

[Shennoz]

Okay I get it now. Basically raster effect resolution is set at the artboard size I'm working on and becomes static. It squeezes & stretches depending on whether I scale down or up my PDF afterwards. Perfect!

I used to think that if I scaled down a high-res raster image (let's say 300dpi) in my design (0.625m x 2m artboard) & save/print as PDF, then when the print shop scales it back up for the final print size (2.5m x 8m) it would lose it's quality. From all the answers here I see I was mistaken and PDF format actually protects the raster resolution. Good to know.

Thanks again

[Jacob Bugge]

For my part you are welcome, Shennoz.

[Danny Whitehead.]

Ask the printer what scale they prefer, and save as PDF, don't print to PDF. They won't be expecting 1:1 for jobs that are larger than the maximum page/artboard size of the commonly used design programs.

Take that scaling, and the likely view distance, into account when deciding your raster resolution.

[Test Screen Name]

A practical limit for PDF files is 5 metres, because Acrobat won't work with bigger. So people with large format printers are used to scaling all the time. Just be sure you let them know clearly the scale. Wouldn't hurt to include it in the file name.