Nodal Point
Definition
The optical centre of a lens from which perspective relationships are computed. Panoramas must rotate around the nodal point to avoid parallax-induced stitching artefacts near foreground objects.
- Definition
- Optical centre of a lens, perspective is computed from it
- Relevance
- Panorama stitching at a crime scene
- Failure mode
- Parallax-induced artefacts near foreground objects
Common questions
Why does rotating around the wrong point ruin a scene panorama?+
Rotating around the camera body or tripod centre instead of the lens's nodal point shifts the apparent position of nearby objects relative to distant ones between frames, producing ghosting or misalignment that stitching software cannot fully reconcile.
Is the nodal point fixed for a given lens?+
No, it shifts with focal length and focus distance on a zoom lens, so a panorama rig calibrated for one setting may need re-calibration if the photographer changes zoom or refocuses mid-sequence.
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