eli5: is a video more accurate than 2 mirrors facing each other?


Today I put up a mirror at a 90 degree angle to another mirror in order to “un-reverse” the reflection, my face looked absolutely other-wordly bad, it looked very skinny, but when I look in the mirror my face looks normal.

After that I took multiple videos using my phone’s camera and the result looked more or less the same as when I look in the mirror(without the 90 degrees thing), So now I’m kinda left confused.


What I’m getting at is the following, with the two mirror method my face looks skinny and that doesn’t make sense cuz in videos and pictures my face looks normal, so now I’m kinda freaking out over this.

In: 0

The proportions of your facial features will depend on the distance you’re viewing your face from. There isn’t really a “more accurate” one. Using two mirrors means you’re viewing your face from “further away” than the distance the phone is viewing your face when taking a selfie.

If you’re using a front-facing camera, many of those will flip the image. You can manually flip it yourself, or use the rear-facing camera if this is the case and it should look the same as the two mirror method.

Note that if your 90° angle was really 89°, that would make your face look skinnier than it is.

I wouldn’t say one is necessarily always more accurate than the other, they both have flaws, it just depends on how much.

A digital camera has all sorts of processing done on it, limitations in the sensor, limitations on the display output etc that change the image from what it looks like in real life. Front-facing phone cameras will flip the image to mimic a mirror, hopefully you factored that in before setting up this 2-mirror experiment. Many phones also include image processing enabled by default to make faces look better, smoother, younger, remove imperfections etc.

A mirror theoretically more accurately reflects (ha!) the image that occurs in real life since there’s no technology involved to screw it up, just the laws of physics. But no mirror is perfect. Impurities in the materials can alter colours (most mirrors have a slightly green tint) and some mirrors may not be completely flat – any minor convexing or concaving will distort the image (making you look skinnier, fatter, shorter, taller than reality). Department store mirrors may even be deliberately designed this way, to help sell clothing.

The best way to tell which one is more accurate in your particular case would be to conduct a survey with a group of neutral observers, comparing both the mirror and camera images to their direct observation of you.