How does Cornflower blue (No.20 E 51) by BS 4800 compare with Johnstone's’s closest paints? The nearest match by perceptual distance is Johnstone's Ocean Horizon (ΔE 1.5, “near-identical”). 3 more Johnstone's colours sit within ΔE 4 — close enough that the difference is hard to spot once paint’s on the wall. These 4 Johnstone's paints are all priced at £12.36 per litre.
BS 4800 Cornflower blue vs Johnstone's
4 closest Johnstone's matches ranked by ΔE
ΔE (CIEDE2000) is a perceptual distance metric — lower means a closer match. Matches under ΔE 2 are typically indistinguishable; ΔE 2–4 looks “the same” once dry on a wall; ΔE 4–6 is noticeable side-by-side. Always view a sample pot before committing — screen colours and lighting vary.
| Colour | Number | ΔE | Match quality | Price/L | Price/m2 |
|---|---|---|---|---|---|
| Ocean Horizon | — | 1.5 | near-identical | £12.36 | £2.06 |
| Bluebell Valley | — | 2.2 | near-identical | £12.36 | £2.06 |
| Victoria Blue | — | 2.5 | near-identical | £12.36 | £2.06 |
| Boudoir Blue | — | 2.5 | near-identical | £12.36 | £2.06 |