Switching from PDF/x1a to PDF/x-3...what do i need to know?

[Andy_Baz]

For may years now i have religiously been using PDF/x1a for outputting files to my Harlequin RIP based workflow, and i have now recently been compelled to bring my self up to more modern standards (with great thanks to Bob Levine and Dov Isaacs).

I am now curious as to the benefits of switching from PDF/x1a to PDF/x-3.

The work intended to test this on is all in house created for in house presses, using InDesign CC 2018.

Any pointers or guidance would be greatly appreciated.

[Andy_Baz]

Kit Specs as follows:

> iMac 5k retina (2015)

> Adobe CC 2018

> Harlequin RIP  V7.1r0 (badged as Momentum RIP from Presstek)

> Dimension 400 Platesetter

> 4 Colour Komori Lithrone 26 press

> 5 Colour Hans Gronhi 525 press

> Epson 7800 Proofer

[BobLevine]

Why X-3? X-4 is the most modern spec.

[Andy_Baz]

I'm open to all suggestions but my previous encounters with Live Transparencies and my RIP have not been great, in that jobs that contain Live Transparencies take forever to RIP, and block the whole workflow queue.

However I am willing to proceed with guidance to remedy such issues.

[BobLevine]

I’m going to bow out, then. That’s not my area of expertise.

[rob day]

I'm open to all suggestions but my previous encounters with Live Transparencies and my RIP have not been great, in that jobs that contain Live Transparencies take forever to RIP, and block the whole workflow queue.

The obvious difference between X-1a and X-3 is X-3 allows RGB objects in the PDF while flattening transparency.

So X-3 would allow you to delay the conversion of RGB objects to CMYK until output assuming No Color Conversion is set in the Output tab at export. That might be a better approach if you are getting CMYK images that have been converted to the wrong profile, but then you might also encounter clients who expect you to print out-of-gamut RGB colors.

There's another more subtle difference. With X-3 if you choose to convert to a CMYK destination in the Output tab that is not Document CMYK, all of the CMYK color will get the output intent's ICCprofile embedded. With both PDF/X-4 and X-1a the InDesign native colors are exported as DeviceCMYK (no profile). I think the assumption even with X-4 is that if you have converted everything into the Output Intent's CMYK space all of the color should be DeviceCMYK and doesn't need anther conversion.

[Dave Creamer of IDEAS]

PDF/X-1a = Transparency flattened and color converted at creation of PDF. User is responsible for creating "good" PDF.

PDF/X-3 = Transparency flattened; color left as is. User is responsible for flattening; RIP is responsible for color conversion. Benefits included more accurate color conversion, especially if using custom printer color profile.

PDF/X-4 = Transparency flattened and color converted in RIP. Benefits include trapping occurs BEFORE flattening happens, and better color conversion.

It really comes down to if your RIP can handle the process. Usually up-to-date RIPs can process files without issue (assuming it is set up properly.) If you haven't upgraded your RIP in a while, you may have problems.

[rob day]

PDF/X-4 = Transparency flattened and color converted in RIP. Benefits include trapping occurs BEFORE flattening happens, and better color conversion.

Just to clarify, X-4 does allow you to make the final conversion on export—you can export a PDF with live transparency where all of the color is DeviceCMYK.