A museum object may be photographed on a stand or inside a frame that makes its dimensions difficult to judge. Catalogue measurements can also refer to different parts of an assembly. Read the measurement labels before comparing numbers across records.
Identify the measured component
Look for phrases specifying height, overall height, framed size, or a separate part. If the entry gives several measurements, preserve their labels rather than copying only the largest number. A support may belong to the object’s history or to its modern display; do not assume which without documentation.
Use the stated units consistently. Converting a measurement is straightforward only after you know what was measured. More decimal places do not resolve ambiguity about the component.
Compare equivalent dimensions
For a small research exercise, choose two records and write one sentence describing each measurement. If one gives an overall assembly and the other only the main object, explain why a direct size comparison would be misleading.
Keep any visual estimate separate from catalogue data. Perspective and cropping can make a photograph persuasive without making it a reliable measuring tool. A careful dimension note is modest but valuable: it tells the next reader exactly which physical extent your comparison concerns.