Define which hand evidence matters
A task may require seeing a reaching hand, the contact point, or both hands coordinating around an object. These are different requirements. Describe the events that must be observable and whether gloves, tools, or sleeves affect interpretation. A statement that hands appear somewhere in a clip says little about visibility during the important interaction.
Review the whole movement
Check the approach, contact, manipulation, and release rather than reviewing a still frame. Objects can hide fingertips at exactly the moment of contact, and hands can disappear below the camera during work near the torso. Identify whether a label remains supportable from adjacent frames or whether the event should be marked as uncertain. Review whether the fingertips and contacted surface can be distinguished separately.
Separate natural occlusion from capture loss
A hand behind a workpiece is a property of the scene; a lens covered by clothing is a capture problem. Record the difference so the collection can retain realistic difficulty without accepting preventable failures. Avoid requiring unnaturally staged gestures unless controlled demonstrations are part of the brief, and document any staging that is introduced.
Match visibility to labels
Hand boxes, segmentation, pose, and contact labels require different evidence and review rules. Ask how annotations continue through partial or complete occlusion and whether left and right refer to the participant. Review borderline examples with the annotation guidance before expanding a collection. A visible hand alone should not be treated as proof of a successful object interaction.
Review checklist
- Name required hand events
- Review near-body and edge-of-frame work
- Distinguish occlusion from obstruction
- Define uncertain and out-of-view labels