Don't believe your eyes ......

[Chris_F]

...... when looking at this picture.

http://mysite.freeserve.com/Bombay_Low/illusion.jpg

A friend sent me this by email. The tiles on the A and B squares are exactly the same colour! And they are!!! [img]/infopop/emoticons/icon_confused.gif[/img] I loaded the image into Paint Shop Pro and sure enough, I get RGB values for both squares of R107,G107 and B107. In Xara if you cut out the A square and move it adjacent to the B square you will see that the colour match is exact. I'll never trust my eyeballs again!!!!

There's a bit of info on this illusion here

http://www-bcs.mit.edu/people/adelso..._illusion.html

Yes, I know this post is not exactly a Xara subject, but anyway...

[pduggan]

It is amazing, but it's been popping up on bulletin boards all over the place including this appearance in the test forum here! The linked flash movies demonstrating further similar illusions are also well worth a look.

Peter

Peat Stack or Pete's Tack?

PS A small point perhaps, but IMHO it's better practice to link to the original than to copy the graphic to another server. Now of course I don't know whether that was done before or after you received the image, but you'll notice that the author's name has been removed from your version, which would upset me if it was mine!

[This message was edited by Peter Duggan on October 12, 2002 at 07:37.]

[jamesvalue]

Hi ,
I just swapped the two squares , and it's really incredible!

http://utenti.lycos.it/jamesvalue/swap58.jpg

Bye

[molucca]

There are only two colors. The board is red and the cylinder is green (hue=100). It appears that they have the same saturation, but vary in value. Rich

[Gaussian]

Impressive! [img]/infopop/emoticons/icon_biggrin.gif[/img]

[molucca]

I made color maps so you see it for yourself. RGB numbers were always a mystery to me. However, after studying Gary's tutorial on gold colors, I saw the connection between hue and RGB. Rich

[Egg Bramhill]

Never understood the RGB channel splitting either.
So I thought I'd try and reproduce it in XaraX. you only have to use 3 shades of grey.
Attached xar file with my effort.
Egg

[Egg Bramhill]

....by editing the grey colours

[molucca]

I though I would look to see if there was some trend in the values. So, I read the image into XPal and created a PAL file. Since the PAL is really a txt file, I read this into a spread sheet, and sorted by R,G,B in that order. Then plotted the data. The plot was pasted into Power Point, ungrouped (to convert to PP objects, and saved in WMF. I then read the wmf into Xara X. Actually, just seeing if the method worked. From XX, the file was exported to a JPG. I haven't determined what it means, however. Rich

[Egg Bramhill]

The spots don't change colour...you can see the middle dot disappear.
Egg