Big Dipper vs Sea Mariner
Both from Sherwin-Williams's palette. These are both blue-greys, so the question isn't which hue to choose — it's where within blue-grey to land. They have nearly identical light reflectance values (6 vs 7), so they'll read as similarly Dark in most lighting conditions. Big Dipper runs neutral while Sea Mariner is decidedly cool, which means they'll respond very differently to warm vs cool light sources. The ΔE 5.2 gap is real but not dramatic — close enough to use together, distinct enough to matter as a choice. Below you'll find 1 real-room photo comparison where both colors appear side by side, plus 5 simulated room previews.
Big Dipper vs Sea Mariner in Real Spaces
1 real room side by side. Big Dipper and Sea Mariner are close enough that the difference can be hard to judge from a chip alone — these photos show how each reads at scale, across different spaces and lighting conditions.
Mudroom
Mudrooms are seen in passing, often under whatever light comes through the door — a context that favors colors with some depth. Big Dipper reads more restrained here, while Sea Mariner adds a sense of enclosure and warmth.
Color Details
Big Dipper vs Sea Mariner Simulated Comparison
5 simulated room previews — drag the slider on each to see Big Dipper on one side and Sea Mariner 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.