By making these changes to my Overdrive "Input Profile" settings, will this affect my RGB images workflow/output in any way?
Just asking because when I was on the phone with Colorburst last week they recommended that I change my "CMYK Image" settings under "Input Profiles" in the RIP to ColorBurst GRACoL G7.icc, Absolute Colorimetric, with BPC off.
I appreciated the advice and have been doing test prints with the "new" settings and my "old" settings.
From what I've seen, all the test prints with the "new" settings come out a little "washed out" as compared to prints using my old settings of "US Sheetfed Coated v2", Relative Colorimetric, with BPC on.
I especially notice the difference in the darker colors and especially the blacks. My "old settings" seem more "saturated", "darker".
Why would the colors print differently after changing just the CMYK settings in the RIP and all my test prints consist of only RGB images placed in InDesign and sent to the RIP?
[/size][/b](note: this is without making any changes in the Adobe color settings yet)
After excellent tech support from ColorBurst I believe we can answer these questions and provide a little insight to how Overdrive works.
All the answers and info were provided from Larry at ColorBurst and with permission are offered here to anyone interested.
If you already knew all this great. If not, I hope this info helps. It greatly helped me!
The answers were provided in separate emails and separated below by dashed lines.
There may be a little repetition in some of the answers because I did not edit any of them, just pasted as is.
Please comment if any of this info did help, or to offer any other info, observations or opinions on this topic.
Thank you.
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Depending how you create a Job to print, your RGB images may be getting changed to CMYK before Overdrive gets the file.
Properly saved, the RGB data will Never be dependent on the settings of the CMYK Input Profile.
From your App, Save as a PDF with the settings of:
- High Quality Print
- PDF Standard = None
- PDF Format = 1.6
These settings will leave your RGB images as RGB.
They will not be converted to CMYK and therefore they do not reference your CMYK Input Profile.
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The above settings:
- leaves Pantones as Pantone (not process color)
- embedded profiles stay embedded (printing from the App loses the embedded profiles)
- RGB and CMYK stay in their original colorspace
- transparencies stay live (not flattened).
Save these files to our Hot Folder or to a Folder to drag to the Job list.
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Now that I understand that you are placing RGB images in your InDesign docs, I can explain a bit more.
If your RGB Images are placed TIFFs or JPegs, then printing from an Application may change the data to CMYK.
The settings above indicate that no color changes should take place and in most, but not all cases, there will be no change.
Even though the RGB color is not being changed to CMYK they will lose their embedded ICC Profiles.
Printing to PostScript does not include embedded Profiles because the PostScript language does not define them as part of the PostScript file, therefore they are discarded.
Printing to PostScript will also flatten transparencies. This is due to the fact that the PostScript format predates the existence of transparent data.
When you have an RGB Tiff and a CMYK dropped shadow, these are typically a transparent blend of different colorspace elements.
Printing will flatten these to the CMYK document colorspace. This causes the RGB image to become CMYK and therefore it will lack in its color richness.
Or worse, the RGB & CMYK intersection will be one color and the rest of the RGB image, that is outside the intersection box, will be another color.
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Saving to a first generation PDF with the settings of High Quality Print, PDF Standard = None, and PDF Format of 1.6
leaves all embedded profiles in the document and all transparent elements in their original colorspace (LIVE) for Overdrive to resolve.
Overdrive does an excellent job of handling the intersection of different colorspaced transparent elements and it will correctly
locate and use the embedded ICC Profiles if our Use Embedded option is ON.