Are These Lines Straight?
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This Demonstration shows a combination of Hering's and Zöllner's illusion. You can see whether the lines are straight or not by moving the "thickness of red lines" slider.
Contributed by: Osman Tuna Gökgöz (March 2011)
Open content licensed under CC BY-NC-SA
Snapshots
Details
M. Bach, Hering Illusion.
Permanent Citation
"Are These Lines Straight?"
http://demonstrations.wolfram.com/AreTheseLinesStraight/
Wolfram Demonstrations Project
Published: March 7 2011