Cool Optical Illusion

[ThaSaltCracka]

to be honest with you, I misred the thing the first time I looked at it. I have no idea how there is a hole there. Please explain, perhaps via PM?

[jdl22]

This one is easy. Her hair is a metaphor for a waterfall. How do I see this? Well it's wet firstly, as is her shirt. Secondly you can see that her head is tilted in such a way so as to appear to be falling straight down as if a waterfall.

[kyro]

TSC,

I remember staring at this for at least an hour before I either finally got it, or someone gave me a hint and it dawned on me. It's pretty neat.

If tyfromm hasn't pm'd you yet, let me know and I will.

[Number4]

There's a waterfall?

[ThaSaltCracka]

yeah he told me. Pretty damn tricky, not sure how I would have gotten it if he hadn't told me.

[Lazymeatball]

Spoiler
Ok. I think I got it. The answer lies in the fact that the two triangles do not have the same slope. The red triangle has a slop of 3/8 = 3.75, while the green triangle has a slope of 2/5 = 4. This difference is farily undetectable neglecting the use of the grid pattern, so most people just assume they are the same. Do I have to explain further for full credit?

[Leo99]

I got the triangle illusion right away but even with Granny's hint I still had to print it and get scissors and cut it out. I still can't believe it.

[LondonBroil]

I would also like someone to pm me the answer to the triangle one, or at least post the reason in white.

[tyfromm]

Here is the original thread with several explanations in white text.

And here's another subtle optical illusion: