Cosmic Blue vs River Valley
Where Cosmic Blue belongs to Behr's range, River Valley is a Dulux color. These are both blues, so the question isn't which hue to choose — it's where within blue to land. Cosmic Blue (LRV 47) reflects noticeably more light than River Valley (LRV 44), a difference of 3 points that becomes especially apparent in rooms with limited natural light. Cosmic Blue runs blue while River Valley is decidedly cool, which means they'll respond very differently to warm vs cool light sources. The ΔE 8.1 gap is real but not dramatic — close enough to use together, distinct enough to matter as a choice. Below, 5 simulated room previews show how each color reads at scale — real-room photos will be added as they become available.
Color Details
Cosmic Blue vs River Valley Simulated Comparison
5 simulated room previews — drag the slider on each to see Cosmic Blue on one side and River Valley on the other.
Digital color is approximate. These simulations are generated from the manufacturer's hex values and overlaid on grayscale room photos — your screen's calibration, brightness, and viewing angle all affect how they render. Before committing to either color, test physical samples in your own space under the light you actually live with.
More Cosmic Blue comparisons
See how Cosmic Blue stacks up against other well-photographed colors across different brands and tones.
