I loves me some optical illusions. I’ve seen so many I can’t remember them all. But this one may be just about the coolest I’ve seen on teh intertoobz. If you play with it for a minute or two you’ll see how it works, and at what speed to drag the stripes over the pattern to make the best animation (it’s slower than you think). It’s very cool.
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November 24th, 2008 at 5:03 pm
That’s way cool. I want to see more of them.
November 24th, 2008 at 5:10 pm
That’s backwards – you should drag the animation past the stripes so the tiger actually runs across the screen!
November 24th, 2008 at 5:56 pm
Bah, the dragon illusion at Grand Illusions is far getter, and shows you how it’s done (and how you can make one yourself)
http://www.grand-illusions.com/images/articles/opticalillusions/dragon_illusion/dragon_illusion.wmv
November 24th, 2008 at 5:58 pm
Oh, that is very cool!
November 24th, 2008 at 6:13 pm
Phil Plait: “I loves me some optical illusions.”
So, how clean is your mind?…
November 24th, 2008 at 6:50 pm
Apparently, it varies from one second to the next
November 24th, 2008 at 7:15 pm
Wicked cool! Never seen anything like that.
November 24th, 2008 at 7:18 pm
Pfft, that ain’t no tiger, it’s a puma.
IVAN, I see your … lamp… and raise you some dolphins (there are 8 dolphins in this pic):
http://pixdaus.com/pics/Bjfe1TvnXTeFYEe7We.jpg
November 24th, 2008 at 7:21 pm
Um… er… nice lamp…
Slightly OT, some canuck videoed the tool bag…
http://www.smh.com.au/news/home/technology/with-the-right-tools-you-can-find-anything/2008/11/25/1227491514585.html
Actually it raises a questions. There is no way the shuttle would change attitude to grab the bag presumably but could it chase down an astronaut who drifted away similarly to the tool bag?
November 24th, 2008 at 7:25 pm
Clockwise or anticlockwise?
[img]http://www.theness.com/images/blogimages/spinning.gif[/img]
November 24th, 2008 at 7:29 pm
Aw shucks!
Here’s the blog post:
http://www.theness.com/neurologicablog/index.php?p=27
November 24th, 2008 at 7:37 pm
Sure — assuming the on-the-spot cost-benefit analysis values the astronaut at more than a $100,000 tool bag. (I guess it’s a good job that the costs of years of astronaut training and the additional costs of damage limitation after not saving their life are so high).
November 24th, 2008 at 7:45 pm
@Mus:
Hey how did that get by the spammo-filter?
November 24th, 2008 at 8:06 pm
Hmm, looks like it’s from the book “Gallop” by Rufus Butler Seder. It’s a cat.
Great book. My kids love playing with it.
November 24th, 2008 at 8:08 pm
There’s a whole series of books for sale now that uses this kind of optical illusion. They’re called “Scanimation.” Very cool!
Never considered that you could do the same thing on a website. Clever!
November 24th, 2008 at 8:18 pm
Mus, I see your… er… 8 dolphins.
Michael, I wonder how a cat/dog would react to that dragon illusion? Probably will spook them!
November 24th, 2008 at 8:24 pm
If you are really old (like me) you might have had a cardboard zoopraxiscope as a kid. Much less capital investment than a computer! Self-powered.
November 24th, 2008 at 9:05 pm
Magnus, if you want to post an image here, you have to use HTML tags, e.g., “< "” & “>”.
The required syntax code is: *img src=”yourURL.com” alt=”image name here”/*
N.B. Replace the * with < at the front, and > at the end. Also, you must enclose the “URL.com” and “image name” within quotation marks.
November 24th, 2008 at 10:05 pm
Or agnnus could just cut and paste the image source into the post and let the BA spam filter hold it til it’s checked out by the BA
November 24th, 2008 at 10:05 pm
Arghhh Magnus… sorry, I have a new laptop and the keyboard is very sensitive
November 24th, 2008 at 10:28 pm
ERRATUM:
Magnus, if you want to post an image here, you have to use the HTML tags: “< " and ">“.
The required syntax code is: *img src=”yourURL.com/image.jpg” alt=”image name here”/*
N.B. Replace the * with ” < " at the front, and " > ” at the end. Also, you must enclose the “URL.com/image.jpg” and “image name” within quotation marks, and no space after the “< " tag nor before the ">” tag . It is not necessary to include alt=”image name here” and can be omitted; however, in case the image fails to load due to server/bandwidth problems, it does serve the purpose of informing the viewer what he/she should be seeing.
I trust this is clear now.
November 24th, 2008 at 11:23 pm
Micheal L, I’ve had similar problems with an over-sensitive touch-pad on my note-book computer. Try using Firefox 3.0.3 browser; its security feature can be set so that it will block any submission with a security warning until you press the “confirm” button. Alternatively, write out your comment on WordPad first, then, when you have finished writing/proofreading, copy and paste your written comment into the comment box and then, after one final spell-check (with Google toolbar), submit the bloody comment. Either of those two options will save you a lot of frustration.
November 24th, 2008 at 11:37 pm
I count nine dolphins.
November 25th, 2008 at 12:40 am
;p
November 25th, 2008 at 2:05 am
Autumn, I had another look and, yes, there are nine dolphins (my mind must have been distracted earlier), and also there appears to be at least one fish in the mouth of the dolphin at the top and to the right of that picture.
quasidog, this is how that emoticon, that you had attempted, is done: colon “:” and upper-case “P”, e.g.,
, and voilà… 
November 25th, 2008 at 2:43 am
IVAN3MAN said:
The required syntax code is: *img src=”yourURL.com/image.jpg” alt=”image name here”/*
Hmm…let’s try an experiment:
<img src=”yourURL.com/image.jpg” alt=”image name here”/>
When I submit, I’ll find out whether IVAN3MAN really needed to replace the angle brackets with asterisks, or could have used the “<” and “>” entities instead.
November 25th, 2008 at 3:37 am
Wow. The optical illusion has turned into an HTML lesson
That illusion is obviously a bouncing tigger!
November 25th, 2008 at 4:14 am
Woah.
[/keanu]
November 25th, 2008 at 4:20 am
How clean is my mind?….. apparently not very…….
November 25th, 2008 at 6:15 am
Bouncing tiger? Where’s Calvin?
November 25th, 2008 at 8:44 am
[...] This has seriously got to be one of the coolest optical illusions I’ve ever seen on the web. Drag the lines slowly for the best results. Link via Bad Astronomy. [...]
November 25th, 2008 at 8:56 am
pbs.org/independentlens/atomsmashers/
Is this really bad to post something that is very off topic again? Sorry, but if you’re a science geek check out the newest documentary from PBS. “The Atom Smashers”(!). It’s about Fermilab trying to find the Higgs.
Leon Lederman is a character in it people (the coolest modern day scientist on the planet-hands down- and has the best sense of humor).
November 25th, 2008 at 9:42 am
Another book.
http://www.amazon.com/Magic-Moving-Images-illusions-Illusions/dp/1899618740/ref=sr_1_1?ie=UTF8&s=books&qid=1227631239&sr=8-1
A little spendy for what it is, but I got on special at a local store.
Bouncing tiger? Where’s Calvin?
Or Winnie The Pooh.
November 25th, 2008 at 10:09 am
What Dolphins? Or am I looking at a different picture?
Is it because I’m Down Under, and all the dolphins are out of the water?
Just thought I’d ask.
Ivan.
November 25th, 2008 at 10:13 am
Or is it a case of “Dolphindoilia”?
November 25th, 2008 at 11:49 am
In what way is this an “illusion”, and not just a clever hack?
Unless you consider something like a flip-book animation to be
an illusion of motion, this seems like just a cute way to deliver
a sequence of images that behave exactly as you would expect.
November 25th, 2008 at 1:34 pm
Bill, now why the bloody hell didn’t I think of that!
icemith, I was referring to the picture via the link provided by Mus.
November 26th, 2008 at 9:07 am
Ah, point taken , IVAN3MAN. Yes it is intriguing and clever. Is it really an old painting/photo/vase or whatever? Thanks for pointing it out.
Actually it reminds me of a time when at school nearly 60 years ago, when I came to my fellow class-mates, and I think some slightly older fellow students, and they had been looking at a drawing, (pencil, as I remember), of an Indian Chief. I only had a brief glance at it before it was rolled-up, but I thought (imagined?) that it was somewhat more than bawdy.
To this day though, I have no idea what it really was, that was “hidden”. If anything. But I can’t imagine what they would have been so interested in, being normal kids, growing-up.
Maybe it is a case of xxxxxdoilia.
Ivan.
November 26th, 2008 at 12:24 pm
I would like to recommend http://www.planetperplex.com
November 26th, 2008 at 9:36 pm
Not really an illusion, though – it’s just a way of delivering animation frames isn’t it?