I had a bit of spare time on my hands at lunch and created a little JavaScript application of the Bent Lines Illusion I blogged about earlier which was a re-post of this Richard Wiseman blog post.

The application allows you to change the orientation of the black diamonds by clicking on them which makes the perfect grid of squares look really weird.

The application can be played with HERE

Try changing a straight line of them right through the middle to start off with to see how the effect works. Remember that the squares are all equal, straight edged and perfectly aligned!

I have tested it in FireFox 3, Google Chrome, Apple Safari 4, Internet Explorer 6, 7 and 8 and it seems to work fine in all of them except IE6 in which it works but incredibly slowly. Please give any bugs, comments or suggestions as comments to this post.

Richard Wiseman re-posted another great optical illusion this morning which was tweeted to him by @ButMadNNW and @glennbroadway. I think it was originally posted on this interesting looking blog called Things You Wouldn’t Know If We Didn’t Blog Incessantly.

The illusion shows a grid of light and dark squares and at each corner there are 2 black diamonds positioned either vertically or horizontally in an alternate fashion, this is except in the middle, both vertically and horizontally. The ensuing effect is the squares appear bent and like the whole shape is bevelled inwards (or outwards depending on your point of view). It really is quite an impressive effect.

I noticed on the image that the black diamonds didn’t quite line up with lines Wiseman put in to demonstrate that the squares were indeed squares, and thought maybe this was part of the effect, someone else on Wiseman’s blog also noticed this so I recreated it making sure everything was perfectly aligned. The effect still worked.

Original Bent Line Illusion

First Version of the Bent Line Illusion

Bent Lines Illusion With Diamond

What is cool about this illusion (especially now I have my Photoshop patterns set up) is that I think it would be possible to put a simple image into it by changing the orientation of the black diamonds. I will have a play and maybe re-post later.

Thank you Richard and the guys that originally posted this! I love a good optical illusion.

I took the Bar Contrast Illusion a step further and made this

I know this is yesterdays news now but I thought I’d finish off something I was working on.

This uses the same principles as the other illusions I posted only there are 2 different intensities of the purple and orange stripes. I also changed the direction of some of the lines to highlight areas of detail. I think it works but then I have been staring at it for a while.

I think I am done with this illusion for now. I hope you like it though.

EDIT: Stepping back and having another look at this I think the Higher Contrast Purple and Orange stand out to much for the effect but I still think it looks pretty cool.

A while back Richard Wiseman posted an excellent optical illusion on his blog here. It looks like a green, blue and pink stripy spiral when in fact it is a turquoise, purple and orange spiral. The difference in purple and orange make us perceive the turquoise differently making it appear either blue or green.

He started making his own one of a world map which you can see here which is pretty impressive. I decided to make a few of my own including a higher resolution version of his world map.

Do you see green land and blue water or orange land and purple water?

An Orange Butterfly

A Green Butterfly

What do you think?

I know that the last one wasn’t done very well, there was a small filling issue when I changed the Hue and Saturation but you can still get the idea.

EDIT: Would just like to say a big thank you to Richard Wiseman and John Matson @ Scientifig American. This illusion got picked up by them and I had a great response, a bit of a supprise. It has been posted here on the Scientific American Gallery