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Friday

Ponzo Optical Illusion

The Ponzo illusion is an optical illusion that was first demonstrated by the Italian psychologist Mario Ponzo (1882-1960) in 1913. He suggested that the human mind judges an object's size based on its background.

The typical example of this is the figure below. This is the typical railroad track scheme usually used to represent this illusion. The vertical lines appear to go off into the distance like train tracks. This gives us the impression that the line in the distance is larger then the line that appears to be nearer to the viewer.

Ponzo Optical Illusion

Mario Ponzo
1913

Seeing this illusion against a great real photo backdrop can be amazing. Most of the time people pick train tracks. Below is an outstanding photo that presents this optical illusion slightly different...

The two red lines (or three if you move your mouse over the image) below are duplicates, they are the exact same size. Which image is more convincing the one with two lines or the one with three lines?

Ponzo Illusion
(c) 2006 Walt Anthony

Project: Create your own illusion. Here is a suitable image of train tracks (right click and select "save target as" or "save link as" depending on your browser). You can use Windows Picture and Fax viewer to print it out.

Now that you have it printed try and create your own illusion.

Use 2 Popsicle sticks painted red or just draw red lines with a marker.
Does changing the color change the effect?
Does using two different colors alter the illusion?
Try fat and skinny lines. Does the thickness of the lines affect this illusion?
Vary the distance between the lines, does this change the effect?
Is a three dimensional Popsicle stick as effective as 2 dimensional red line?
Does the distance from which you view the illusion change the illusion?

What can you conclude, if anything, about how we perceive things from this project?


38 comments:

Anonymous said...

hey..........these are some cool illusions.....wow...i really enjoyed them...

Anonymous said...

THese r ok.

Anonymous said...

COOL ILLUSIONS! BUT I ALREADY KNOW THE TRACK ILLUSION!!

Anonymous said...

Cool! I didn't believe it at first!

Anonymous said...

i am not trying to be funny or owt but these r a bit boring ..... soz

Anonymous said...

cool but these not many and there a bit boring

Anonymous said...

i dont get it they are all the same size!

Anonymous said...

i didnt get half of the ! sorry better luck next time.

Anonymous said...

that train station one was impossible! i was like 'what!? those lines are not the same size!' but apparently they were!

great job!

xx

Anonymous said...

u sicken me.

Anonymous said...

completely stupid.
your terrible.

Anonymous said...

my favorite part was when he grabbed the ice cream!!!!


<3 this

Anonymous said...

i love you

Anonymous said...

crap!!!!!!!!!!!!!!!!!!

Anonymous said...

crap!!!!!!!!!!!!

Anonymous said...

these are a piece of shit

Emma said...

well i like these but they arent hard and they arent fun and theres not enough!!

Anonymous said...

this whole website is dum

Anonymous said...

this is retarded
why did you even make this site

Anonymous said...

these illusions are cool

Anonymous said...

I thought these illusions were very cool make sure and post more!!

sam said...

These are a bit confusing to me

Anonymous said...

you are all so negative be positive. Great job on the website, the illusions are amazing.

Anonymous said...

i really do like pie hi grace have you told him our secret yet

Anonymous said...

I love these illusions, I could hardly believe the lines were the same size but I measured them and they are!!!

Anonymous said...

i like illusions alot! but i like the spinny vortex thing, wich for SOME REASON isnt on this site

Anonymous said...

This is alright. I figured out everything in a flash, though. Make them harder next time! <3 Sorry!

Marcello said...

hii i like chocolate and strawberries do u like chocolate and strawberries sorry im not this crazy im just really bored hehe lol rotf lmao rotflmaoqwerty again! i am really bored but about these optical illusions they arent that challenging:(

wakkoyakkodotslappy said...

ooooooooooooooooooooooooh. aMAZing! i like the motion ones. and remember, kids, Yakko backwards is OKKAY!

Katie Kaboom said...

I love optical illusions.

thejetsons&casper&yakko said...

oo oo oo! more more more!!!!!!!!!!pppppppppppppppplllllllllllllllllllllleeeeeeeeeeeeeaaaaaaaaasssssssssssseeeeeeeeeeeeeeeeeeee

Anonymous said...

...these are a bit weird illusions i think there are better ones though

Anonymous said...

Heeey, i Love Illusions but some are sooooo Rubbish So..... Try Get Better ones, ill be Back Next year In 2012 !!! XXX <3 Facebooks Better Than Dis !

Anonymous said...

this things are so unbelievable,but at the same time they are epic!!!!!

Anonymous said...

i love josh wood
<3

Anonymous said...

wow. these are A.M.A.Z.I.N.G...lol jks..

Bob said...

not bad. You could REALLY use some help at making a cool website. Cause this website is not.

Anonymous said...

ohnestly i dont get it


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