Color difference between window and windowsill

Will never match completely. Even a powder coating with the same powder on steel and aluminum will have a slightly different color. Different gloss levels also make the color appear different. What you also have here are two different coating processes. When in doubt, always compare samples, but keep in mind that there can also be slight variations from that.

Other materials that is why it looks different

Aluminum and plastic always look different, the aluminum is painted, the plastic window is foil-coated, it cannot look identical. Don't worry, the dark windowsill will be dusty after a week anyway, so it will look different again.

Best regards
Sabine

normal! see no objection there.

These are plastic windows and aluminum window sills.

That is also the whole reason. Because: RAL is not Pantone. A RAL color tone only indicates what color the paint or other coating has - not how the finished treated surface appears.

I thank you very much for your opinions. Then I will probably have to accept it. Thank God it is only the case in the [OG], since we have a clinker roll layer in the [UG]. If I saw that every day from the outside in the [EG] in summer, I would freak out...