Preparation for Color Separation

In recent times, I have received several pieces of “finished art” supplied by clients where the sales representative has informed me that the printed material must be “on-brand” according to the client’s style guides. That should be the end of the story, but upon checking the finished art, it is clear that the artwork has not met the client’s own style guides, or been thoroughly checked by the client prior to submission.

One of two things will now happen – the prepress department can either fix the artwork without disturbing the client in order to fulfil the brief and expedite the work, or we can contact the client informing them of the situation and THEN ask whether we can fix it or have resupplied artwork that is color correct. Considering that the client may receive their proof and resupply the artwork in its entirety, this means fixing the colors again.

For years, I’ve been an advocate of receiving finished artwork that is correct for the following reasons:

  • The client has correct content;
  • Eliminates the risk of human error in prepress from incorrect or unintentional manipulations during corrections;
  • Prepress can output more work considering they are not spending time manipulating files that may only be replaced at a moment’s notice;
  • My employer isn’t losing revenue on prepress time that usually is not passed onto clients by the sales representatives.

That said, I make sure to contact customers who have supplied finished art that is incorrect and outline the issue, giving them the opportunity to resolve the issue themselves or let us do it. It is at this stage where some customers have been willing to fix the artwork themselves, but cannot see the issue. When I ask them to check the separations preview panel, the answer is always the same – “where’s that?”. Because this is a panel that I use so often as a prepress operator, I often think to myself “are you kidding me?” but to be fair, there are many panels in InDesign that I don’t use such as the animations panel; and I would have no idea how to use either.

On that note, I have prepared a video on my Youtube channel on how to use the Separations Preview within Adobe InDesign and used it to highlight instances of color mismatches, issues with black ink, and when white overprints.

This is not the first time I’ve been on my soapbox about this before – (see this article). It also directly relates to:


I’m gonna knock you out, my printer didn’t knock you out…

An earlier post “To Overprint or not to Overprint, Black is the question” explains how the colour labelled [Black] in InDesign behaves, and when solid black ink should and should not knock out of the colours behind it.

Paying attention to this advice and applying it to artwork should result in a good printed reproduction, correct? While the answer should be yes, there is one more level of control of black appearance and overprints, and that is in the hands of the printing company and their output software.


Let us look at this following example:


This card is set up for a Black plus spot output for an offset press. The Black is only overprinting on the text as misregistration would be noticeable here, but the Black elsewhere is knocking out so that the colour does not look muted through the yellow.

However, despite best intentions and checking the separations both in InDesign and Acrobat, the card has printed like this (effect is exaggerated for the screen):


So what has happened? The separations were correct, they were checked in both InDesign and Acrobat! It turns out that the Raster Image Processor (RIP) software that the commercial printer uses to image the design onto the printing plates has its own settings. Here are some example screenshots from AGFA’s Apogee X system and Fuji’s XMF system respectively about the overprinting of black:



In both screenshots above, the respective RIP software CAN honor the settings that were in the initial PDF and not apply its own preferences, but in the instance of the business card, the RIP settings overrode the PDF settings and chose to overprint all instances of 100% black, regardless what swatches were chosen in InDesign.


Using the same artwork, the card was printed via a colour copier, but this time the result was as follows:


So what happened here? The while the solid black looks good, where the black in the top line meets the vignette looks rather weak, and there are is a lighter black around the travel agent. What is going on?

Again, the RIP software has manipulated the artwork with unintentional results. Unlike printing directly to a desktop printer, most digital printers will print to a RIP where the file can be imposed, colour adjusted and printed in whatever order the prepress operator sees fit.

Using the EFI Fiery RIP, there is a little-known feature of the RIP that changes the way black is displayed that can produce unexpected results, and that is in the color settings dialog box and it is “Pure Black On”.

Screen Shot 2013-06-03 at 2.55.28 PM

This setting takes every instance of 100K and ramps the colour to a “super black” as opposed to using the black toner only. Again, this setting can be changed, but when this card was printed, the defaults were unchanged resulting in this unwanted appearance.

This setting only applies to vectors and text AFTER the PDF is flattened into postscript. This is visible where the rich black abruptly changes to the muted black. One look at the flattener preview in InDesign confirms that areas of flat black in that image were as a result of the flattening.



This small example shows how changing the client’s intended black overprints can have unwanted consequences. For prepress operators it is a wake-up call to make sure that the RIP defaults will maintain the clients’ expected results; and for designers or publishers it is worth understanding that even the treatment of black overprint is an important topic.

Identifying bad links when InDesign doesn’t

A recent post “No Links Stinks Methinks” highlighted the issues with cut and pasted objects into InDesign, namely:

  • The link would not appear in the links palette;
  • The link would not appear missing in the [Basic] preflight; and
  • The link could not be edited to fix any prepress issues

The example used in the post was simple enough – one image placed in a one page InDesign file. In this example, it was simple to determine that the image was clearly missing its link as it was the only image there and should have shown up in the links palette.

The article concentrated on the fact that the images had no links, rather than an effective method of finding badly linked images. Looking for images with no links is fine in a small file, but in a large document that has hundreds of pictures such as a school yearbook, finding these “bad links” are much harder – looking for images that don’t appear in the links palette can be time-consuming and prone to error.

Luckily, Rich from Kerntiff Publishing has a free script that behaves in a similar fashion to the links panel but with one exception – it shows links that are bad:

imagenavUnfortunately, resolving the link issue is the next problem. But at least knowing where the images appear is half the battle.

In the interests of full disclosure, I have no commercial interests in the script, nor Kerntiff Publishing, and no money changed hands to publish this article.

No links stinks methinks

Recently, my colleagues and I have noticed several InDesign files supplied by clients that contain images that do not appear in the links palette. This creates issues because:

  • The image cannot be edited
  • Its details (resolution, colour space etc) cannot be determined through the links palette
  • Its high-res appearance or PDF output can change from how the image appears in standard preview in InDesign.

When I tried to replicate this fault (having an image with no link in the links palette), the consistent way to achieve this fault was to cut (or drag) content from one application and paste it into InDesign.

To demonstrate this, I have dragged an image from my Facebook page into InDesign. This is how the links palette looks in InDesign:


Note that the links palette shows no link, so I have no mechanical information about the link from the links palette. When I right click on the image I can’t edit the image from the contextual menu.

Now, if I place the original image from my hard drive using the File/Place command, I can now see the information about the link from the links palette and I can also edit the image from the contextual menu.


This is where cut and paste (or drag and drop) can become confusing. If I drag the image icon from any folder using Finder (on a Mac) or Explorer (Windows) the image appears in the links and is editable.


However, if I open Photoshop, select all with my marquee tool, copy and paste (or drag and drop) into InDesign, again no link/edit menu is the result. SO NO GOOD!


This example is using only one picture, but imagine a parts catalogue or any other picture-rich content that may have this issue.

Disturbingly, it doesn’t show up on the [Basic] preflight profile, nor does it show up as an issue in the package feature.


However, if use a decent preflight profile such as VIGC_v2.0_Prepare for Sheet CMYK_1v4, it does show up as an error, but only for its resolution and not its colour format.


Ultimately to avoid this situation, the best solution is to avoid drag/drop or cut and paste between applications.

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