Calculate Height of a Person from Object?

Is it possible using an object whose height we know precisely, to figure out the height of a person within a photograph?

In this short video below, I try to use a DVD that I'm holding to figure out my exact height. Since we know the actual height of the DVD to the mm, and of course I know my own height too, surely this should be simple

I mean just how accurate could it be?

If you watched the video above, then you can see that we are several inches off and the reason is that camera lenses can distort images. In order for the principle to work you'd need to have a sufficient distance and lens settings (focal length) so that there was a minimal distortion present and an object that measured a certain length in the middle of the photo, would also look the same at the top and bottom of the frame.

In a similar vein, if we are also comparing height and people are different distances from the camera, we could potentially be underestimating a person slightly further away, or overestimating somebody closer to the camera.

Consider the image below. I am 175cm plus carpet/board, which puts me around 177cm.

Rob and object

The camera is near 10 feet away from me. The silver cupboard behind me is about 11 inches behind and measures 174cm.

A 3cm difference in height has become a lot greater in the photo as a result:

Rob and object cupboard

Add a Comment1 comments

J2Frenzy said on 30/Oct/20
Yeah according to my dad’s doorframe I’m 6’3+ at 1pm. I’ve never been that tall

Heights are barefeet estimates, derived from quotations, official websites, agency resumes, in person encounters with actors at conventions and pictures/films.

Other vital statistics like weight or shoe size measurements have been sourced from newspapers, books, resumes or social media.

Celebrity Fan Photos and Agency Pictures of stars are © to their respective owners.