Viewing distance

The measured separation between the observer or camera and the glass during a stated inspection.

Meaning and boundaries

There is no single universal viewing distance for all glass products, defects, restoration diagnostics, or final acceptance.

Why it matters in glass restoration

Distance changes which features are visible and is essential for reproducing before-and-after comparisons.

Related terms

• Viewing angle
• Lighting condition
• Acceptance criteria
• Condition photograph

References

• ASTM International — ASTM C1036-25: Standard Specification for Flat Glass
  Publisher’s original source
• National Glass Association — Guidelines on How to View Decorative Glazing Products
  Publisher’s original source
• ASTM International — ASTM C1376-21a: Pyrolytic and Vacuum Deposition Coatings on Flat Glass
  Publisher’s original source