For JPG images that are inserted into Layout as an external drawing, significant color changes occur after publishing to PDF via Publisher.
In Archicad Layouts, JPGs appear the same compared to the source file, but the PDF export from Publisher is significantly color-shifted (both in terms of color tone and image brightness). The output is completely unsatisfactory, a PDF with embedded images cannot be presented or printed seriously in this state.
I did a small test to demonstrate the problem. In Layout, I created colored rectangles as fills, made a printscreen of them and inserted a printscreen next to the original. I attach the test result in the attachment.
On Windows everything is all right, Its only MAC Silicon issue. The issue also occurs in AC27 MAC and maybe in older versions?
OK. Head spinning a bit from experimenting in the mad science lab. Bottom line is that it has nothing to do with your Mac being Silicon vs Intel, but everything to do with (a) using the built-in screen capture on a Mac and (b) the 3rd party PDF driver that Graphisoft uses does re-interpret the color space in the color profile.
After verifying that I see what you see... and measuring the colors with the built-in Apple "Digital Color Meter" (which I encourage Mac users to take advantage of when trying to color-match anything)... some Googling shows that graphic artists have problems with the macOS built-in screen capture function as it captures colors as interpretted by the active monitor color profile. I verified this by changing my monitor profile to several others (which were ugly but anyway) seeing that the Digital Color Meter indeed measured different RGB values for the red that was supposed to be (255,0,0). Wildly different in fact.
In reproducing your screenshot issue - pure color fills, screenshot, drag screenshot back in as a placed drawing... I saw a similar (but different) color shift as you did. Not exactly the same as my monitor profile would not match yours. Opening the screenshot in Preview and using Digital Color Meter gave me the same colors as appeared in the layout in Archicad.
Digital Color Meter can use multiple color spaces. In Native Values, the red wasn't even close to (255,0,0), but in sRGB ... even though the pen is set to pure (255,0,0), the meter reads (255,1,0). Instead of (0,0,255), pure blue reads as (8,0,255). Pretty close anyway...why not exact is a small mystery.
On the drawing that was saved as a screenshot ... the PNG image (I set my screenshots to save as PNG instead of JPEG for better quality) and the placed drawing have identical - but different - colors. The pure red swatch became (235,8,17), green did not shift... (1,255,0), and blue (15,0,255). Almost no shift to CMY and gray. That difference from yours is purely up to the color profile of my monitor. Totaly weird... but this is on Apple, not Graphisoft. In the Graphic Artist community, the advice is to take any screenshots received from clients... all of whom would have had different monitor profiles... and export them from Photoshop to jpegs with the option to convert to sRGB. That seemed to work.
Anyway... that explains ONE part of the color shift.
Part TWO of the color shift is the 3rd party PDF exporter that Graphisoft has incorporated into Publisher. It, too, takes the monitor profile into account and converts the colors - whether we want it to or not... of images that contain both a color space and monitor profile. And, unlike image files, I haven't seen a way to undo this conversion. Somewhere in that PDF export, there may be a setting that Graphisoft can tweak to have it not do profile color conversion and to leave the pure RGB/CMYK values that are in the Layout. Like you, I consider this conversion of colors a bug. And, because this software is only part of the Mac version of Archicad, that's probably why you don't see this happen under Windows.
To clarify: in my experiments, the pure RGB solid fills exported to pure RGB in the PDF whether I used File > Print >Save as PDF or Publisher. But, it was the screenshot image that had its colors shifted...not just upon creation... but upon Publisher generating the PDF....as if the monitor profile was applied again. Save-as-PDF did not shift the placed image's colors again.
Summary...
1. Shifted colors of screenshots dragged into Archicad are an Apple problem and the colors have to be restored using a Photoshop export if placing screenshots onto Layouts with accurate colors is important.
2. Shifted colors of images containing monitor profiles in Published PDFs is a Graphisoft problem and they have to work with their 3rd party PDF routine provider to address that. Any colors generated by pens in Archicad do publish with their desired color values. The issue is only images contained on the layouts.
...at least in my analysis this past hour 🙂
PS. If you do a Get Info (cmd-I) on the screenshot jpg (png for me), you'll see both the color space and the color profile such as the below screenshot. When I changed my monitor to different profile settings, that showed here... and the color shifts differed. I have no idea why Apple thought this was a good idea.
I did the test again without using printscreen, so as not to involve Apple's bugs in the problem.
I created the right part of the image by exporting the left part from AC using Command+P > PDF > Save as PDF. I converted the PDF to JPG in MacOS and then inserted it as an external drawing into AC. Then I published the whole thing using Publisher to PDF. Compared to the previous test, slight deviations to other shades has almous disappeared, but the changes in darkness remains above the tolerable limit. It is very strange that the shift in darkness is different for each shade, some are almost identical, while the further away from the basic RGB shade the more pronounced the deviation.
I would like to disagree that this is not a critical issue. Many of us use AC as a tool for architectural work, where layouts contain a large number of visualizations and other images, and this is a really big problem not only for interior projects. I looked at the released AC 28 hotfixes, no fix was important for me (I didn't notice any stability problems either), fixing this problem is absolutely crucial for my work.
I am adding a test with more colors, basically all are affected except for the basic RGB colors, where the deviation is tolerable.
