How to Picture Light

I don't know why, but I've never really 'understood' light, in general. I know all of the details, how lenses work, reflection, diffraction, refraction, parallax, blah blah, but overall I couldn't actually Picture it very well in my head. I won't go too deeply into light, there's a lot to it. There's colors and frequency and different reasons different things are different colors. I'm just concerned with light in general here, and that's how I'll treat it. I always had questions like: If light spreads out the farther away from an object it gets, then how does perspective work? Wouldn't it almost seem that objects should look Bigger the farther away from them you are? And I understood how an image gets inverted through a lens; for those who don't know, I'll explain it briefly. Ever taken a photography class, and had it explained to you how a image gets inverted through the camera, and is "upside down" when the film's developed? Or ever heard about how images come through your retina, and are actually "upside down" when they get to your brain? Then it goes that your "brain has to 'flip' it" so that you get experience down as down, and up as up. The camera analogy goes, a lens is curved like this:

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so any light passing through the bottom of the lens gets directed "upwards" and any light hitting the top of the lens gets diverted "downwards" kinda like this:

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So, since the light that hits the bottom of the lens is directed "up" and vice verse, you get an inverted image on the film.

It's not the best explanation, but I hope you can picture what I mean. So, understanding how a lens flips an image, something still didn't make sense. Pinhole cameras are said to invert images, too. Those are the science project cameras, where you simply get a box, poke a hole in one side, cover the hole, put some film inside the box, and then you uncover the hole for a few seconds, cover it again, develop the film, and you have a picture! But still, there's no lens here, only a hole in a box. What special properties does the hole have that inverts an image when it comes through?

I had all these weird ideas, about how light hitting the edge of the pinhole would "curve around it" kinda like pressurized water going through a small hole, stuff like that. Either way, it just never quite came out right in my head when I tried to picture it.

The first clue to my understanding of light, came when I started to learn about how holograms work. Nobody ever really seemed to be able to exactly explain it to me, but every explanation always had something like "every part of the image, is made up of the whole image" and other odd things like that. This started to make sense to me, if every part of the light reflected off of an object looks like the whole object, I can start to fill in a few of the pictures in my head. That would explain things like: why a star billions of light-years away still looks like a circular star on earth when we're only looking at an extremely tiny, tiny, fraction of the light cast off by that star. But still, how can you picture this "every part of the image looks like the whole image" stuff?

Let me give you an example of why this "every part of the picture is the whole picture" thing was a clue that set me off in the right direction to understanding light. Ever do the classroom projects to view an eclipse through a pinhole? How does that work? Not only that, but have you ever seen the light shining through trees during an eclipse? There's all these little eclipse-shadows on the ground! Ever wonder what was up with that?

To finally understand light, I had to go through a little thought experiment in my head. First, picture some round ball or something. Keep it one color, like a solid red ball. So now you're looking at this ball a few feet away from it, maybe five feet. You can see the ball, it's smooth, it's red, it's round, etc, you're looking straight at it. Now get a little closer to the ball, maybe a foot away. It's bigger now, but it's still smooth, bright, maybe you can catch a little shine from one part of it or something. Now get closer still, maybe an inch away. From here you can't really see the whole ball, only a portion of it. But you can start to see that it's not quite smooth, it has a little bit of texture on it, you can see little hints to small bumps and imperfections it may have. Get closer, still. Now you're looking at it like through a magnifying glass.

You can't see the whole ball, it's a smaller portion even still, filling up your whole vision. With this view, you can see that it's not only a few small bumps, it's a whole lot of tiny little bumps, each one you can see in 3d, like a basketball up close. Closer.

Now you're so close that it's like the view through a powerful microscope. You're only looking at a few of the "bumps" now, but you can almost start to see that these bumps are kind of made up of bumps themselves. Get closer. You're looking at the individual molecules that are making up the ball now. We're not going to get any closer than this to understand light.

So you're looking at these molecules, they still look like small spheres, we're not close enough to atom level. Now, from this perspective, picture light reflecting off of these tiny, tiny, tiny spheres. Reflecting off in all directions. You can change your view to look around the small spheres, and you can 'see' a solid sphere of light reflecting off of them, every direction, up, down, left, right, every point in between. You can picture it a bit like the Everlasting Gobstopper's diagram, where there's a small candy "core" (your molecule), and then the sphere around the core. except that this "sphere" extends infinitely outwards from the molecule. Now take a step back.

You're looking at many molecules now, picturing this "sphere of light" around each one. Lets say you're looking at six molecules, stacked two on two on two, and you're looking at the direct center, in-between the two in the middle row. So, since you're looking at this exact angle, picture only the light that will "get to" you from that angle and you'll notice: You're only 'seeing' parts of the each of the molecules "light spheres." From the top left molecule, you're only seeing the light