Foreshortening - mirror vs photo/video

  • Context: High School 
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Discussion Overview

The discussion revolves around the concept of foreshortening as perceived in a mirror compared to a video or photograph. Participants explore how distance and angles affect the perception of body parts, particularly when approaching a reflective surface versus a camera.

Discussion Character

  • Exploratory, Conceptual clarification, Debate/contested

Main Points Raised

  • One participant questions whether there is more foreshortening when viewing oneself in a mirror compared to a video or photograph, particularly when approaching the mirror.
  • Another participant asserts that an image in a vertical plane mirror is not foreshortened, as the distance to the image is equivalent to the distance from the viewer to the mirror.
  • A follow-up post considers the angles involved, suggesting that the perception of knee height might differ based on the angle from the eyes to the reflection in the mirror versus viewing an identical twin at a distance.
  • Another participant clarifies that viewing oneself in the mirror is akin to observing an identical twin at double the distance, implying that the perceived angles may not differ as initially thought.

Areas of Agreement / Disagreement

Participants express differing views on the effects of distance and angles on perception, indicating that the discussion remains unresolved regarding how foreshortening is experienced in these different contexts.

Contextual Notes

There are assumptions about the nature of reflections and the angles involved that remain unexamined, and the discussion does not resolve the complexities of visual perception in these scenarios.

JohnJa
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Hi,

Is there more foreshortening when I look in the mirror than when I look at a video or photograph of myself.

For example, if I am naked, or with bare legs, and I walk towards a mirror, will my knees look lower to me than if I watch a video of myself walking towards the camera? (assuming the camera is at my eye level.)

And if so, which of these two perspectives more closely represents reality? / Represents what another person would see as I walk towards them?

Thank you.
 
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I don't know anything about distortions introduced by video, but your image in a vertical plane mirror will not be foreshortened. If you are x feet from a plane mirror, your image (identical in size to the original you) will appear to be x feet on the other side of the mirror (that is, 2x feet away from you).
 
Thanks Doc Al,

I was thinking that if my image in the mirror is 2x feet away, but the angle from my eyes to the reflection of my knees would still be equivalent to the angle at x feet, then that might make my knees seem lower?

Or is the angle from my eyes to my knees in the mirror less steep than it would be if I was looking at my identical twin at x feet? Because my knees are effectively 2x feet away?
 
Looking at your image in the mirror (when you're x feet from the mirror) is exactly like looking at an identical twin standing 2x feet away.
 

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