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What Do Cats See?

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Re: What Do Cats See?

#51

Post by jere »

earlz wrote: post #50
Aco- wrote: post #48

Earlier quoted context omitted.

For the lazy programmers who don't want to write some quick JS to simulate what a dichromat perceives as green: http://ill.cc/colorz.html click on the page, toggle between red & green with any keypress

If you're on a mobile device without a keyboard, I made an alternative version that changes on click rather than keypress: http://jsbin.com/iPIrucU/1

Derp. I figured someone else would beat me to it. Press or click. It goes through 3 contrasting pairs (based on the wikipedia article):

http://jere.in/opponentprocess.html

Re: What Do Cats See?

#52

Post by arketyp »

rxzv wrote: post #49
arketyp wrote: post #45

Earlier quoted context omitted.

You might be interested in what is called opponent process theory of color vision.

I know I can google it, but is there a particular link you recommend to read up on it?

As it happens I was just researching it myself (it was briefly mentioned in a lecture on scientific visualization). I found this (have not read yet), what seems like a thorough and serious treatment of the subject.

http://www.handprint.com/HP/WCL/color2.html#heringtheory

Re: What Do Cats See?

#53

Post by anigbrowl »

chatman wrote: post #11

I have seen my cat find a mouse in a camouflaged garden even when the mouse was not moving. Either this study is wrong or my cat is special.

The mouse wasn't moving that you could see. Consider that a mouse has a much higher heart rate; if you can pick one up (eg those rare occasions where you are able to rescue prey from the cat) they practically vibrate in your hand.

Also, another poster makes a good point about cats' hearing. Not only do cats hear in higher frequency ranges than we do thanks to their reduced size, they can angle their ears to 'focus' on a particular sound; being a sound engineer by profession, I desperately envy them this ability. I have simulated this using cardioid microphones while wearing headphones, and I would cheerfully sacrifice a good deal of social standing for a pair of working prehensile ears.

Re: What Do Cats See?

#54

Post by Someone »

carlesfe wrote: post #42
jobigoud wrote: post #13

I think there is one fundamental flaw with simulating color seen by non humans or dichromat humans. I've seen this in all computer based simulators. They simply change the weight of some colors relatively to others. But a dichromat with say, missing L cones will not simply mix green and red, he will experience "green" totally differently than a trichromat. What a trichromat call green is the result of the stimulation…

Oh, wow, thas was an incredible experience, thanks! In trying to explain it some way... the green was SO GREEN that it actually looked like it was flashing blue. By the way, is there any other similar experiment I could try?

For some definition of 'similar': http://www.scientificpsychic.com/graphics/

Re: What Do Cats See?

#57

Post by roryokane »

dTal wrote: post #5

The trouble with "simulations" like these is they ignore cognitive post-processing - much like visualizations of what it's like to look through a compound eye portraying it as like looking at a wall of TV sets. The human images and the cat images are not comparable because the human images represent a subjective impression, rather than a prediction from visual capabilities like the cat images. For example, the human…

I think these simulations are after post-processing. That us exactly why the human vision picture is sharp past 6 degrees from center - the picture portrays what we see after our brains stitch together a visual field.

Re: What Do Cats See?

#59

Post by angersock »

mikeweiss wrote: post #39
ecopoesis wrote: post #33

Scientists at Berkeley have actually recorded what cats see by scanning a vision pathway in their brain: http://www.berkeley.edu/news/media/releases/99legacy/10-15-1... Here's a link to the video: http://www.youtube.com/watch?v=piyY-UtyDZw

What the hell did they do to that cat! :-(

It's a cat scan.

Re: What Do Cats See?

#60

Post by mratzloff »

SeanDav wrote: post #44

This seems to answer a question I asked myself just yesterday: A neighbour's cat and my cat had a argument, no actual fighting - just lots of staring, yowling and that strange growling sound cats make. Nothing too questionable there, but then my cat did something rather strange - she started moving away by walking extremely slowly and I mean extremely slowly. I wondered what on earth she was up to but after reading t…

I suspect not. To do so would imply that cats are self-aware, which no one has been able to demonstrate.
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