Undercover vs Thunder Gray
Where Undercover belongs to PPG's range, Thunder Gray is a Sherwin-Williams color. These are both greys, so the question isn't which hue to choose — it's where within grey to land. They have nearly identical light reflectance values (10 vs 9), so they'll read as similarly Dark in most lighting conditions. At ΔE 2.7, these are close — the kind of difference that matters when choosing between them, but doesn't read strongly in a finished room. Below you'll find 4 real-room photo comparisons where both colors appear side by side, plus 5 simulated room previews.
Undercover vs Thunder Gray in Real Spaces
4 real rooms side by side. Undercover and Thunder Gray 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 two are close enough that the choice comes down to finer qualities — undertone, texture, what the color sits next to.
Bedroom
The context that matters most in a bedroom is how a color reads under a bedside lamp at night, not under noon daylight. At this scale the difference is subtle — you'd need them side by side, as shown here, to reliably tell them apart.
Kitchen
In a kitchen, colors are seen under bright task lighting that amplifies undertones — what reads neutral elsewhere can show its hand here. At this scale the difference is subtle — you'd need them side by side, as shown here, to reliably tell them apart.
House
Seen across an entire facade, subtle tonal differences become pronounced. What reads as nearly the same on a chip often reads as clearly different at scale. At this scale the difference is subtle — you'd need them side by side, as shown here, to reliably tell them apart.
Color Details
Undercover vs Thunder Gray Simulated Comparison
5 simulated room previews — drag the slider on each to see Undercover on one side and Thunder Gray 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 Undercover comparisons
See how Undercover stacks up against other well-photographed colors across different brands and tones.
Ammonite reflects far more light (LRV 69 vs 10), opening up a space where Undercover encloses it.
At LRV 83 vs 10, White Dove is decisively the brighter choice.
A 4-point LRV gap (10 vs 6) makes Undercover the marginally brighter of the two.
Purbeck Stone reflects far more light (LRV 52 vs 10), opening up a space where Undercover encloses it.
Evergreen Fog reflects far more light (LRV 30 vs 10), opening up a space where Undercover encloses it.
At LRV 52 vs 10, Mizzle is decisively the brighter choice.
Agreeable Gray reflects far more light (LRV 60 vs 10), opening up a space where Undercover encloses it.
At LRV 58 vs 10, Accessible Beige is decisively the brighter choice.
At LRV 27 vs 10, Denim Drift is decisively the brighter choice.
French Gray reflects far more light (LRV 43 vs 10), opening up a space where Undercover encloses it.
Undercover reads slightly lighter (LRV 10 vs 4), a gap that shows most in low-lit rooms.
At LRV 55 vs 10, Tranquil Dawn is decisively the brighter choice.
A 3-point LRV gap (13 vs 10) makes Bancha the marginally brighter of the two.
At LRV 44 vs 10, Hardwick White is decisively the brighter choice.
Pure White reflects far more light (LRV 84 vs 10), opening up a space where Undercover encloses it.
Artichoke reads slightly lighter (LRV 21 vs 10), a gap that shows most in low-lit rooms.
At LRV 66 vs 10, Balboa Mist is decisively the brighter choice.
At LRV 74 vs 10, Shoji White is decisively the brighter choice.
At LRV 83 vs 10, Snowbound is decisively the brighter choice.
Pigeon reflects far more light (LRV 51 vs 10), opening up a space where Undercover encloses it.
Their light reflectance is nearly identical (LRV 12 vs 10), so neither reads brighter in a room.
Their light reflectance is nearly identical (LRV 10 vs 8), so neither reads brighter in a room.
At LRV 68 vs 10, Skimming Stone is decisively the brighter choice.
Dix Blue reflects far more light (LRV 41 vs 10), opening up a space where Undercover encloses it.
Their light reflectance is nearly identical (LRV 12 vs 10), so neither reads brighter in a room.
At LRV 45 vs 10, Saybrook Sage is decisively the brighter choice.
Pale Green reflects far more light (LRV 31 vs 10), opening up a space where Undercover encloses it.