No More Low Res RGBs! Setting up a simple Preflight in InDesign CC
Today I’m going to show you how to setup a Preflight Profile in InDesign to catch any low resolution and/or RGB images.
If you’ve spent any time preparing InDesign documents for print you’ll know that one the easiest ways to screw-up the final result is when low resolution images slip through the net. Hopefully, you’ll be working with a decent print supplier who’ll have their own procedures in place to catch these, but that may not always be the case and even when it is you’re still losing time and money through unnecessary revisions. Thankfully, InDesign comes with a Preflight tool that can be customised to search for specific file issues.
Let’s start by calling up the Preflight Panel – go to Window>Output>Preflight. Now go to the Panel Menu icon and choose Define Profiles… from the drop-down menu.
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Down the left side you’ll see a list of the current profiles available. Click on the ‘plus’ symbol below this to add a New Profile.
The ‘Profile Name:’ input field allows us to name the profile and the ‘General’ section has space for a description – this is useful if you manage lots of different profiles or intend exporting profiles to use on other machines.
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Under each section there are checkboxes and/or text input fields to specify the file attributes that a profile will check for. For this profile I am only interested in checking Resolution and Colour so will disable everything else.
In the example below the horizontal line through the ‘LINKS’ checkbox indicates some of the options are selected so these need to be unchecked. To select or deselect all the sub-sections in a category click on the main checkbox – this will turn all options on or off.
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Under ‘COLOUR’ is a section for ‘Colour Spaces and Modes Not Allowed’ – here we can specify which colour modes will be flagged by our profile as a potential issue. This applies to any InDesign content and not just Image Links – use an RGB Swatch to colour text, for example, and this will be flagged.
One caveat to that rule is Spot Colours. In commercial Swatch Libraries, such as Pantone, swatches are often specified in Lab or RGB colour for greater accuracy – because these are set-up as ‘Spot’ colours and render to their own colour separation they are allowed to pass by the Preflight Profile unless the ‘Spot Colour’ checkbox is selected. This gives you flexibility over intentional use of Spot Colours. There is an additional section for ‘Spot Colour Setup’ which gives even greater control over spot behaviour.
I’m going to select RGB and Lab modes here – although Lab is less common than RGB it still presents a problem in a print-based workflow. This will warn me if Lab or RGB are used by an image link or any InDesign content such as frames or text.
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Next, I’m going to specify the image resolutions I want to adhere to. Under ‘IMAGES and OBJECTS’ you’ll find the ‘Image Resolution’ section. Here we can specify Minimum and/or Maximum image resolutions that will causes an error to be flagged.
The most common Industry Standard minimum resolutions are 300ppi for Colour and Grayscale images and 1200ppi for 1bit images (or bitmaps as they are often referred to). You may want to work to different values but I’ll assume these settings for the purposes of this demonstration.
We can also specify a Maximum resolution which is useful for monitoring redundant resolution. When large images are scaled down excessively in InDesign the additional resolution will not add any quality to the final output and just means extra image data is being stored and processed needlessly. By setting a cap on the maximum resolution allowed images can be monitored and scaled down accordingly.
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With our options configured we can now click ‘Save’ – our Profile can now be accessed at any time from the Panel Menu Icon.
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In the example below there are a number of issues with this document that our profile has flagged. Under each drop-down in the Error section you’ll see the problem images (or objects) listed. Select one of these and the issue is explained in the Info section.
The orange text to the right side is the page number – this is also a hypertext link so clicking on this will take you straight to the problem image/object within the document space allowing you to quickly remedy the issue.
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The Preflight Panel is also be accessible from the bottom left of the document panel. The document is continually checked against the current Preflight Profile for any errors – you’ll see a red dot and the number of errors listed if any issues are present.
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Because the document is constantly monitored this can cause slow-down when working with long, complex documents, particularly with more complex profiles. Because this profile checks image resolution any time an image is resized it will be reanalyzed against the profile settings.
In my normal workflow I tend to leave the default profile active as this checks for basic issues like missing images and overset text which don’t impact on software performance whilst designing and editing. I’ll only swap to the Colour and Resolution profile later in the workflow when preparing a document for output. Once completed I’ll switch back to the default profile.
With a few simple Preflight Profiles in place it’s easy to take the guess work out of file checking and safe-guard against costly, time-consuming errors.