RAL 660-5 vs Slick Blue
Where RAL 660-5 belongs to RAL Effect's range, Slick Blue is a Sherwin-Williams color. These are both blues, so the question isn't which hue to choose — it's where within blue to land. Slick Blue (LRV 52) reflects noticeably more light than RAL 660-5 (LRV 41), a difference of 11 points that becomes especially apparent in rooms with limited natural light. The ΔE 4.2 gap is real but not dramatic — close enough to use together, distinct enough to matter as a choice. Below you'll find 2 real-room photo comparisons where both colors appear side by side, plus 5 simulated room previews.
RAL 660-5 vs Slick Blue in Real Spaces
2 real rooms side by side. RAL 660-5 and Slick Blue 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.
Living Room
In a living room, color works across both daylight and evening light — the same wall can read very differently at noon and at 8pm. The LRV gap is large enough that Slick Blue will make the room feel meaningfully brighter than RAL 660-5 would.
Bedroom
The context that matters most in a bedroom is how a color reads under a bedside lamp at night, not under noon daylight. Slick Blue reflects noticeably more light off the walls, making the space read more open than RAL 660-5.
Color Details
RAL 660-5 vs Slick Blue Simulated Comparison
5 simulated room previews — drag the slider on each to see RAL 660-5 on one side and Slick Blue 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 RAL 660-5 comparisons
See how RAL 660-5 stacks up against other well-photographed colors across different brands and tones.
White Dove reflects far more light (LRV 83 vs 41), opening up a space where RAL 660-5 encloses it.
A 11-point LRV gap (52 vs 41) makes Purbeck Stone the marginally brighter of the two.
A 10-point LRV gap (41 vs 30) makes RAL 660-5 the marginally brighter of the two.
At LRV 60 vs 41, Agreeable Gray is decisively the brighter choice.
Accessible Beige reflects far more light (LRV 58 vs 41), opening up a space where RAL 660-5 encloses it.
RAL 660-5 reflects far more light (LRV 41 vs 27), opening up a space where Denim Drift encloses it.
Their light reflectance is nearly identical (LRV 43 vs 41), so neither reads brighter in a room.
Tranquil Dawn reflects far more light (LRV 55 vs 41), opening up a space where RAL 660-5 encloses it.
With LRVs of 44 and 41, the two reflect almost the same amount of light.
At LRV 84 vs 41, Pure White is decisively the brighter choice.
Balboa Mist reflects far more light (LRV 66 vs 41), opening up a space where RAL 660-5 encloses it.
Shoji White reflects far more light (LRV 74 vs 41), opening up a space where RAL 660-5 encloses it.
RAL 660-5 reflects far more light (LRV 41 vs 12), opening up a space where Pewter Green encloses it.
Skimming Stone reflects far more light (LRV 68 vs 41), opening up a space where RAL 660-5 encloses it.
RAL 660-5 reflects far more light (LRV 41 vs 12), opening up a space where Vintage Vogue encloses it.
Saybrook Sage reads slightly lighter (LRV 45 vs 41), a gap that shows most in low-lit rooms.
A 10-point LRV gap (41 vs 31) makes RAL 660-5 the marginally brighter of the two.
At LRV 41 vs 7, RAL 660-5 is decisively the brighter choice.
At LRV 41 vs 24, RAL 660-5 is decisively the brighter choice.
At LRV 57 vs 41, Guilford Green is decisively the brighter choice.