Observation, a reasoned hypothesis and a small test form the basis of reliable technical judgement.

Practise these checks

  • Examine the same item under three lighting conditions.
  • Distinguish changes in colour, sheen, grain and structure.
  • Use precise descriptions rather than simply writing dirty or old.
  • Compare before treatment, while wet and after drying.

Learning sequence

  1. Write one condition description each day.
  2. Record your assessment before reading the instructor's conclusion.
  3. Use a small test to evaluate the hypothesis.
  4. Review whether an error arose from observation or execution.

Memorising brands and product names encourages automatic assumptions. Practise across different materials, conditions and cases.