Someone standing upright with their shoulders back will appear taller than the same person standing with slightly bent knees or leaning forward.

Diana’s posture could also vary depending on whether she was walking, greeting someone, standing formally, or posing for an official portrait.

Positioning

Even a difference of a few steps can change how two people appear in a photograph.

If one person stands slightly closer to the camera, perspective can alter the perceived proportions.

If someone stands on a step, curb, slope, or raised surface, the difference can become even more noticeable.

Camera angle

Photographers don’t always shoot from directly in front at eye level.

A camera positioned above or below the subjects can alter the visual relationship between them.

The resulting photograph is therefore a two-dimensional representation of a three-dimensional scene.

What we see isn’t necessarily an exact record of physical proportions.

The Bigger Question: Were They Ever Deliberately Positioned Differently?