Dual Photography

Why HN readers recommended it

Cited whenever threads discuss recovering hidden images or non-line-of-sight imaging, as a clear demonstration of light transport.

This is a summary from the source dataset, not an endorsement by Hacker News or the video creator.

Video & recommendation details

Creator / channel

mm648230

Topic

computational photography

Format

demo

Level

intermediate

HN recommenders in dataset

4

HN mentions in dataset

10

Recommendation years in dataset

2013–2026

These counts and years describe the included Hacker News records; they are not YouTube views or the video’s publication date.

From the original HN conversations

Excerpts from the recorded comments. Follow each source for the full comment and surrounding discussion.

• Dual Photography has always been the optical "trick" that's blown me away. Here's the demo video from Siggraph in 2005: [VIDEO] Skip ahead to 4:19 for a succinct demo.

• This reminds me of dual photography [1], in which you trade many projectors and one camera for one projector and many cameras using time reversal symmetry. The video [2] gives a good explanation, and the revelation of the playing card is what strikes me as …

• It sounds like "Dual Photography". [LINK] "We present a novel photographic technique called dual photography, which exploits Helmholtz reciprocity to interchange the lights and cameras in a scene. With a video projector providing structured illumination, reciprocity permits us to generate pictures from the viewpoint of …