Color changes when copy-n-pasting from one CMYK doc to another

[Stephen_H]

I've made a screen cast video of this so you can see it in action, but simply put, here is my process:

1. Open a CMYK PDF. I confirm the document is still CMYK.

2. Select the orange object. The orange is 5/60/100/5

3. I copy it.

4. I create a new document. It's also CMYK.

5. I paste the orange object into this new document.

6. The orange object now reads as 13/64/100/2

(In the video, I copy-n-paste back to the original document for good measure and the new color mix is retained which makes me suspect it's being copied with RGB values, not the CMYK values)

Why does this orange object change its CMYK colour mix when moving from one CMYK document to another. It's not changing colour models so I expect it to remain the same color mix. Please can someone tell me what I'm doing wrong. When this happens, I can't trust ANY colours in my documents. If I can't copy-n-past a logo from one document to another and keep the corporate colours, I can't use it for professional design work.

Please tell me it's something I'm doing, and not the application that doesn't respect color mixes and converts everything to RGB first.

[Palatino]

Both CMYK documents must also have the same profile.

[Stephen_H]

I see that changing the profile within the document changes the colour reading. Thank you, I'm able to replicate this issue with and without my problem.

However... This is not how a profile should work. A profile should be adjusting the way it is displayed on screen, simulating the final experience, not changing the actual colour mix of the object/pixel/swatch etc.

This is a problem.

[MikeW]

8 minutes ago, Stephen_H said:

I see that changing the profile within the document changes the colour reading. Thank you, I'm able to replicate this issue with and without my problem.

However... This is not how a profile should work. A profile should be adjusting the way it is displayed on screen, simulating the final experience, not changing the actual colour mix of the object/pixel/swatch etc.

This is a problem.

It is an issue. Affinity applications use an output profile in the document setup and, by default, convert in the destination profile.

In the document set up you can choose to assign versus convert.  However, it doesn't work as I would expect and keeps reverting from assign back to convert and thereby altering color values. But I believe it does work if in the document that object(s) is being copied from, to set the button for assign, then change the output profile to the same as the document that will be receiving the objects. That should work.

In short, output profiles should be just that, for output only. There should not be an output profile controlling in-document color in AD or APub.

[lacerto]

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