A mixed-surface sample note becomes more useful when it separates three fields: what was tested, what was visible, and what remains open. The format keeps a quick sample from sounding like a material guarantee or a final specification.
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Use a similar viewing setup when practical, then record any meaningful difference between the samples. If the setup changed, say so plainly. The point is a traceable observation, not a universal result.
Find more cautious test-planning ideas in /updates/.