Ionian vs Thermal Spring
Both from Sherwin-Williams's palette. These are both blues, so the question isn't which hue to choose — it's where within blue to land. They have nearly identical light reflectance values (20 vs 21), so they'll read as similarly Medium in most lighting conditions. Both lean cool, so they'll behave similarly in mixed or changing light conditions. The ΔE 4.6 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
Ionian vs Thermal Spring Simulated Comparison
5 simulated room previews — drag the slider on each to see Ionian on one side and Thermal Spring 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 Ionian comparisons
See how Ionian stacks up against other well-photographed colors across different brands and tones.
At LRV 83 vs 20, White Dove is decisively the brighter choice.
Purbeck Stone reflects far more light (LRV 52 vs 20), opening up a space where Ionian encloses it.
Evergreen Fog reads slightly lighter (LRV 30 vs 20), a gap that shows most in low-lit rooms.
Agreeable Gray reflects far more light (LRV 60 vs 20), opening up a space where Ionian encloses it.
At LRV 58 vs 20, Accessible Beige is decisively the brighter choice.
A 7-point LRV gap (27 vs 20) makes Denim Drift the marginally brighter of the two.
French Gray reflects far more light (LRV 43 vs 20), opening up a space where Ionian encloses it.
At LRV 55 vs 20, Tranquil Dawn is decisively the brighter choice.
At LRV 44 vs 20, Hardwick White is decisively the brighter choice.
Pure White reflects far more light (LRV 84 vs 20), opening up a space where Ionian encloses it.
At LRV 66 vs 20, Balboa Mist is decisively the brighter choice.
At LRV 74 vs 20, Shoji White is decisively the brighter choice.
A 8-point LRV gap (20 vs 12) makes Ionian the marginally brighter of the two.
At LRV 68 vs 20, Skimming Stone is decisively the brighter choice.
A 8-point LRV gap (20 vs 12) makes Ionian the marginally brighter of the two.
At LRV 45 vs 20, Saybrook Sage is decisively the brighter choice.
Pale Green reads slightly lighter (LRV 31 vs 20), a gap that shows most in low-lit rooms.
Ionian reflects far more light (LRV 20 vs 7), opening up a space where Pine Needle encloses it.
Cement grey reads slightly lighter (LRV 24 vs 20), a gap that shows most in low-lit rooms.
Guilford Green reflects far more light (LRV 57 vs 20), opening up a space where Ionian encloses it.