Outlining the problem… text outlining

From time to time, I will prepare PDF artwork for third party providers and then note that their specifications indicate “Convert all text to outlines” (also known as converting to curves or paths). But why do some third parties recommend this practice?

The PDF is opened in software other than Acrobat

For commercial printers, PDFs are usually imported into Raster Image Processing (RIP) software that will impose and trap the artwork for their printing methods. However, not all providers work this way and may need to open the PDF in applications other than Adobe Acrobat. For example, a third party that prepares cutting formes may open the file in Corel Draw or a CAD application that supports its CNC software.

This means that as the file opens, the application may ask for fonts not available to the third party.

This can be exacerbated if the PDF is opened not only in a different application than Adobe Acrobat, but also a different alphabet and writing system. Converting the type to outlines maintains the appearance of the type without requiring the font to be present.

Other reasons that text is converted to outlines

So special effects can be applied

InDesign, Illustrator and Photoshop can apply interesting special effects to vector objects, but not all of those effects can be applied to live type. The solution is to convert the type to outlines, thus converting the type to vector shapes that can have the desired effect applied.

To prevent editing by third parties

Limited editing is possible within PDFs using either Acrobat’s own editing tools or using plugins such as Enfocus Pitstop Professional. These tools can allow last minute alterations to text so long as the text is type and not converted to outlines.

Locking the PDF with password protection isn’t an option as this can prevent the file from being placed into layout software or RIP software for output, so the password is then required to unlock the file. PDF password protection is also somewhat breakable, with many websites offering services where PDFs can be uploaded, and then unlocked and then downloaded without the password protection. There are also PDF editing and viewing applications such as PDF Sam that allow for decryption of PDFs.

Even without the Enfocus Pitstop plug-in, it is possible to open PDFs in Adobe Illustrator or Affinity Publisher and then – if the fonts are available – make the necessary alterations… though converting type to outlines will prevent this.

To circumvent the font EULA

A client may have acquired a font that has allowed for screen use only and prohibits embedding in a PDF, preventing the font from appearing correctly in the PDF. A way around this is to convert the type to outlines in the native application prior to PDF export, though it is worth noting that the End User Licence Agreement (EULA) of the font may forbid this workaround, so it is worth reading the font EULA.

That doesn’t mean it should be done!

There are issues that arise from converting type to outlines. Dov Isaacs – Principal Scientist for Adobe Systems – has a brilliant PDF that details this (and much more) but the basic takeaways concerning type to outlines are:

  • Increased filesize that takes forever to download or view onscreen
  • Smaller typefaces do not render as well
  • May potentially breach the font’s EULA

In addition, there are other issues such as:

  • Potential issues with fonts where type overlaps itself (it can knock out holes in the joins)
  • If the conversion from type to outlines has been done in the native application and then accidentally saved and closed, this means the type will no longer be live in the native application.
  • It can prevent or hinder minor type alterations being made in a PDF submitted for print.
  • Text (as outlines) that has special effects applied (as described earlier) may not always be able to have the same effect applied to live type. This can create issues with variable data campaigns where the effect needs to be applied to a text variable.
  • It can make it difficult to identify the font used, as the font’s information is no longer in the PDF and the only other way to identify the font is visually or with apps such as what the font, adobe capture, or identifont.
  • The conversion is usually a one-way conversion. There is a fantastic Adobe Illustrator plug-in from Astute Graphics called Vector First Aid 2 that – in some circumstances – can convert outlines back to type, but it isn’t a magic bullet (though definitely worth a look).

If your hand is forced…

In a perfect world, I’d only deal with providers that fully supported PDF/X-4 files. Unfortunately, not all providers do, and occasionally our hands will be forced into providing PDFs specifically as the provider has requested, which may mean converting text to outlines. Rather than doing this in the native application (e.g. InDesign or Illustrator) there is a great way to quickly convert all type to outlines using an Adobe Acrobat Preflight that is detailed over at CreativePro.

Lineart vs Greyscale scans for text

When faced with creating artwork a black and white book from a previous print that has no digital artwork available, the fastest and cheapest option is to scan the book. This assumes that there are no changes to the text, that the book is for print only, and that the client has allowed the spine to be cut off of the book so that the pages can scan through a document feeder. If the book is text only with no halftone, I would recommend the scans end up as 1200 dpi linearts. This is fine if the book is text only, but if the text contains images such as photographs, then two scans are required – one for the text (linearts), and one for the images (300dpi greyscales). The two sets of scans then have to be combined by placing the images into InDesign.
One might ask “why not use greyscale scans at 1200dpi”? Apart from the filesize when printing – the text will look terrible. To understand why high resolution doesn’t always equal better quality, the answer lies in one process: Rasterising.
Regardless whether a greyscale scan is 300dpi, 600dpi or 1200dpi, the scan will still have to go through the rasterising stage on the copier where a filter is applied to make the shades of grey that the artwork may contain. This is usually done with a halftone filter in the copier’s RIP software. This is where the images are converted into halftone dots – measured in LPI – Lines (of dots) Per Inch.
nosharper1Using a 150lpi halftone filter, here is what happens when the same images are rasterised (click on the image to see at correct size):
nosharper2The 600dpi and 1200dpi images do look better than the 300dpi, but the type is still not sharp, and looks bumpy. This is because of the halftoning that is occurring in the RIP. Despite the resolution the text was scanned, the bumps on each image are in the same spots in each scan (though the severity of the “bumps” is different with the dpi)
Lineart images are different in that there are no shades of grey, and do not have halftone applied to them. So once passing through a 150lpi halftone filter, here is how the images look after being rasterised (click on the image to see at correct size):
nosharper3Here, the difference in dpi does matter, as the 1200dpi lineart is sharper than the 600dpi lineart, which is definitel­y sharper than the 300dpi lineart
Here is the side-by-side comparison (click on the image to see at correct size):
nosharper4So by creating the book with separate scans for the images and type, the quality will be greatly improved, but will take longer to set up.

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