All right, we are going to tackle aperture. I sometimes feel like aperture might be the most mysterious of the parameters for a lot of people. But it's really not that complicated. I'm going to break it down for you, we're going to go back to our trash barrel analogy with the rainstorm. So now, instead of taking the cover off the trash barrel, we're actually going to cut a hole in the top of that cover, but that hole size is going to be related to our aperture. So let me take a step back.

Aperture is Express also infraction, although it's typically referred to as f 1.8, or F 3.5. And you'll see an F with a slash and the number. Well, that number is actually a ratio. It's one over that number. And so that number represents how large that opening in the lenses so the aperture Is the opening inside of the lens, there's a diaphragm that opens, sometimes it opens just a little bit, sometimes it opens a lot when the shutter opens, so one over 3.5 for an aperture f slash 3.5. That's saying that that hole is going to open one over three and a half of the amount of the total lens opening.

So an aperture of F one would be that thing opening up completely because one over one is one, it's 100% of the opening. But f two is going to be half of the opening. So if you've got a hole this big, then it's only going to open half of that amount and so on as you go up. So F nine is only one nine, and so they start to get really small as you get up into the higher f numbers for your aperture. It's going to start almost looking like a pinhole that's opening up. So, back to the trashcan if we've got one point eight, that's going to be a pretty large opening for your aperture.

So we're going to cut a big hole in that trashcan, and we're just going to take off that part we cut out and say our shutter speed stays constant throughout this illustration. So we've got a one second shutter speed, we take that part, we cut out for one second, and then we put it back on. So we had a pretty big opening, we pilot a decent amount of water. And now, to contrast that with a higher aperture, let's say f 11, we're only going to cut a hole that's one 11th of the entire lid. So we cut our tiny little hole in the middle, and we take that off for one second. And we let the water in and we put it back on.

So obviously in the ladder extra example, f 11. We didn't let hardly any water in. Now again, the water is light in our illustration. So that shows us that higher apertures are going to let in less light. A lower aperture is going to let in more light So the contribution to exposure from aperture is high aperture, darker exposure, a low aperture a brighter exposure. Now, aperture contributes to a very important quality of the photograph, other than how much light it lets in.

So, you've probably seen photographs where backgrounds blurry and the subject is in focus that comes from a shallow depth of field. And a depth of field is simply the area in a photograph that is in focus. Now if the camera is here, photographing me, that slice of infocus runs parallel to the camera lens. Okay, so that slice of focus is essentially our depth of field. So if we have a narrow depth of field, that slice I'm going to turn the slice so you can see it, that slice becomes very narrow. When we have a deep depth of field, that slice deepens.

So when we have a narrow depth of field, or a shallow depth of field, say you're shooting at F 1.4, you could potentially focus on my eye, and then everything behind me and even my nose. It's a little bit above average size nose, but even my nose tip would be out of focus, but my eyes would be in focus because that slice is so thin, running right through my eye. Everything behind me is blurry, everything in front is blurry, and there's my eye sharp. Now, if I wanted to get more focus, I'd go up to say f nine, where that slice of focus is going to deepen and widen. Now my whole body, my nose, tip the back of my ears, everything around me, maybe even the background behind me is going to be in focus. So this is a creative tool that you can harness to change the look and feel of your photographs.

You can adjust your aperture for depth of field but also keeping in mind that is also contribute your exposure. So you do have to balance those things. And we will tie these in more after we talk about ISO until about how to balance them all. So if you want a shallow depth of field, you need to have a lower aperture number, which actually means a bigger opening the lens, it is a little bit confusing, because it's a ratio. So the lower that number goes, the F number, the bigger the opening, because it's actually one over that number. And for you guys that don't like math, you can just block out what I'm saying.

But if you do, you're just changing the denominator. So as that denominator increases, your number actually decreases and vice versa. It's probably more than you want to know about the numbers behind aperture. But again, a quick breakdown. The lower the aperture number, the wider the opening and the shallower your depth of field The larger your aperture number, the smaller the opening your lens and the deeper your depth of field. So, that's aperture, we talked about shutter speed.

And now we're going to talk about ISO. And then we'll tie these things all together. And you'll know the three foundational pillars of creating your exposure and the look and feel your photograph.