Black is an absence of light or no color. An object is the color you see it right now, so at night at very low levels of light all the colors will appear to be darkened or near black. Because all colors converge toward black black is in every color palette as it gets darker, and is the only color that can be mixed into any color scheme because of that fact.If we were to design a room in all black we would not be able to see anything so we mix it with lighter colors against it, and blackened colors. This color scheme is great for rooms such as nightclubs and bedrooms, but in the lighter more contrasty version can be a daytime room as well.
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Blackened Colors
The question with black plus colors rooms is how dark do you want to go.
Effectively black is a clear tone, whose lighter versions are white and gray.
If you throw a lot of white and lighter colors against it you will have contrast.
If you throw darkened colors against it you will have a dark room. If you use the black as an accent color against darkened colors it will be a medium dark room. But you have to have a plan to create a room that has light and dark elements against each other.
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You can see the issue in this purple and black room, where if it gets any darker you would not be able to see, so how much lighter elements against the darker elements plus ambient lighting is up to you. Very often this issue is solved with a lighter floor than the walls, or visa versa.
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This classical bathroom in black and darkened red has a guilded wood molding to add a regal touch, but metallic and glass surfaces as well as ambient lighting,
are musts in dark color rooms.
This living room is medium ground between the dark and the light and is monochromatic blues from pastel to bright to gray tones and then to near black.


Color theory for earth tones