05-13-2013 01:48 AM
Here is an optical illusion I would like to hear some opinions about. The photo was taken by myself.
It is a picture of one of three legs of a clocktower. The legs are curved down and outwards.
The reflection that you are seeing in the leg, is a reflection of the top of the clocktower....twice!
Once facing towards the top and one facing downwards.
There appears to be a "joining" of the two images in the middle.
The question is...."WHY?"
06-13-2013 04:06 AM
The shiny curved surface is acting like a concave mirror (googe concave mirror physics for a detailed explanation with photos). It has to do with how the curved surface reflects light rays to a focal point, past which the reflected image becomes inverted. I'm guessing you were near this focal point, and the varied curvature of the upper and lower portion of the reflective surface in relation to you (the lower portion is closer than the rear and at a steeper angle) caused the upper portion of the surface to be on one side of the focal point and appear upright, while the lower surface is on the other side of the focal point causing it to be inverted.
06-26-2013 06:40 AM
Nicely done, this gave me a physics flashback!!
07-25-2013 09:51 PM
COOL!..... To really "see" this effect, I had to stand on the concrete base that the leg was mounted to, which was probably a good 24" off the ground!....Standing on the ground, the effect was not visible!
06-13-2013 04:12 AM - edited 06-13-2013 04:20 AM
Here's a youtube demonstration showing how the image flips based on whether or not you're inside or outside the focal point.
05/18/2023: New firmware updates are available.
EOS Rebel T100 - Version 1.1.0
EOS 5D Mark IV - Version 1.4.0
EOS 6D Mark II - Version 1.2.0
PowerShot Elph 360HS - Version 18.104.22.168
PowerShot SX420 IS - Version 22.214.171.124
PowerShot 620 HS - Version 126.96.36.199
PowerShot SX720 HS - Version 188.8.131.52
PowerShot G1X Mark III - Version 184.108.40.206
PowerShot G7X Mark II - Version 220.127.116.11
PowerShot G9X Mark II - Version 18.104.22.168
04/20/2023: New firmware version 1.4.1 is available for EOS R3
03/30/2023: New firmware updates are available.
EOS 1DX Mark III- Version 1.7.1
Speedlite EL-1 - Version 1.0.2
03/30/2023: Product Advisory for EF50 F1.2 L USM
03/30/2023: Product Advisory for EOS R10
2/07/2023: New product announcements!EOS R8 EOS R50RF-S55-210mm F5-7.1 IS STMRF24-50mm F4.5-6.3 IS STMRF15-30mm F4.5-6.3 IS STM
Canon U.S.A Inc. All Rights Reserved. Reproduction in whole or part without permission is prohibited.