RE: [Demo notebook] Reference notebook: corrections and recurring beginner questions · RWI-09200

Case 25 — Disputed observation: is this dial colour shift real or just lighting?

The difficulty is that phone cameras adjust white balance automatically, and blue dials are especially sensitive. Two photos of the same dial under different light can easily look like a 'batch difference'. Any comparison needs both dials in the same frame, under the same light, ideally next to a neutral grey or white reference card.