Flattened Layers: What They Are and Why They Matter

Flatten Layers in your file to print like a pro

If you’ve self-published a book or are investigating the idea, you’ve likely come across ‘layers.’ Unless you’ve worked with complex images or graphic design software, there’s a very good chance you aren’t too familiar with layers. 

So, what exactly are layers and why do they matter? What’s the deal with flattening your layers to make a printable PDF?

Print Files Done Right

Lulu—and all the other publishers out there—like to tell would-be authors how easy it is to create a book. I know, I’m guilty of this offense. And, if we want to get technical, publishing today is easy. Easier than it ever has been in the past at least.

But easy doesn’t always mean simple. 

Uploading a file and ordering a bound book from that file is easy. Uploading a file that will print exactly the way you want it to and create your book perfectly, now that’s a challenge. Anyone who has endeavored to print a book knows that laying out your file is an art form.

Helping you demystify the art of book design and formatting is what the Lulu blog is all about! We talk about elements of formatting and how to design a page to fit printer specifications regularly. 

Even still you could get your file designed beautifully, sized perfectly, and looking amazing on your screen and still have issues printing. For an author, getting a proof that looks wrong is one of the most frustrating things in the world. I’ve been there, I know.

Finalizing a PDF

As you complete your book’s interior file, you need to think about how your file will convert to PDF. If you aren’t already aware, PDF is the universally accepted file for printing documents. No matter what file types a publisher offers to accept, always provide a PDF (some exceptions for ebooks). 

I’ve suggested this to authors before and had all kinds of responses tossed back at me. Most are ‘why can’t I just send my Word file’ or ‘I’m not a graphic designer.’ Well, if you’re not a graphic designer, that’s all the more reason you need to know how to best provide files. And if you’re working from MS Word, well then you really really need to know about PDFs.

A PDF as a final product means what you see is exactly what you get. PDFs offer finality and consistency in the file presentation that no other format can rival. Most notable, DOC and DOCX files are anything but consistent, as the file will apply styles and direct formatting based on the source and the version of Word used to view the file. 

PDFs do not suffer inconsistencies based on viewer, file version, or software. The purpose of a PDF is to provide a single, consistent file type for printing. 

What Are Layers?

When you create a document using Microsoft Word, InDesign, and most the like, we make the document using layers. Each element added to the page, like text, images, page numbering, or header styles, is on its own layer. 

Here’s an example looking at our Next Level Marketing Infographic. Created in Adobe Illustrator, I’ve opened the PDF using Affinity Publisher

Visible layers prior to flattening

The menu on the right shows layers, with three primary layers and multiple content layers to complete the infographic. Every piece of text and every image is a distinct layer. I can select individual elements and move them or edit them.

GIF showing the option to select and manipulate individual layers

If I select all the layers and rasterize them, it compresses the layers into a single layer!

GIF showing how a flattened layer appears

Note that using Rasterize to flatten layers isn’t right for all projects. I used it because I can select all the layers and rasterize them quickly enough to make a gif. I don’t suggest going this way to flatten your file unless you’re comfortable rasterizing a file.

Printer Perfect

As you can see in the gif above, after flattening my file, the entire content is a single element. You can likely imagine why this is helpful for printers creating your book. With no layers, we can print the contents with no manipulation or alteration. 

Flattening any layers in your file may not be obvious. It took me a long time to wrap my head around how important it can be. 

Just remember that Lulu (and any other book printer) will need to flatten your file before we can finish printing. If you do that step before submitting the file, you’ve removed one potential snag! And you’ve seen your file in its printer-perfect form so you know it will look good once the book is printed and bound.

Paul H, Content Marketing Manager

Paul is the Content Marketing Manager at Lulu. When he's not entrenched in the publishing and print-on-demand world, he likes to hike the scenic North Carolina landscape, read, sample the fanciest micro-brewed beer, and collect fountain pens. Paul is a dog person but considers himself cat tolerant.

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Could you, please, tell me why I cannot send pdf text files to Lulu made from docx Word files? Only if I convert my docx files to doc files and then convert them to pdf files are acceptable by Lulu. Initially, it took me a month to discover why my pdf files coming from docx files could not be accepted by Lulu. Only after saving my docx files as doc files and then into pdf files Lulu accepted them. The reason was on me? If so, please, tell me what to do in order Lulu to accept my pdf files coming from docx files. Thank you.
Monk Damaskinos

As a newspaper publisher, I have received ads in the PDF format and I learned early on – the hard way! – that what the advertiser sends me is not always what I received.
I learned to take a screen-shot of what I received to send back for approval. That catches missing elements and font substitutions.
A simple way to rasterize a file – I do it with all my Lulu book covers – is to first save the design as a PDF. I then convert it to a JPG, then back to PDF and all the layers are now one. I use a MAC, if that matters.

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