 So have you ever wondered why some of your pictures come out looking too dark or too light, things like that? Well, that is all a matter of exposure. Exposure is defined in photography as the correct amount of light that would fall upon a light sensitive medium and therefore create an image that is, you know, the desired effect of the photographer. So a good example of exposure is that I wanted to expose in the image here to the left for this ice right here. I wanted to make sure that this ice was the right color. Now there was a different amount of light falling on this part of the picture than there was over here back in the background. This is like the shore of a little creek. There were some trees and this was in a shadow. You can see the big shadow there. And so I was exposing for this light right here. There's a different amount of light. And so when I made the photograph, this part is light and bright just the way that my eyes saw it and it's not dark like it is over here. I wanted it to be this, I wanted it to be about this bright. And exposure just has to do with basically with the brightness of your image if you really simplify it down to its very core. Exposure is something that we're going to be talking about in the next few videos here for this course. And it's related to your ISO, to your shutter speed, and to your aperture or depth of field setting. So you're going to be learning about all this stuff in a lot more depth. And there's also going to be a later lesson that's going to dive into detail about exposure. But I just wanted to introduce these terms to you so that you understand a little bit how they're connected before you learn more about them. So first of all, exposure is often said to be in a triangle. We're going to make ourselves a little pink triangle here. And on the top, we're going to have ISO. To the right, we're going to have your shutter speed. And to the left, we're going to have your aperture. So your ISO is the speed of your film. It's not sped, it's speed with two E's. The speed of your film or your sensor. And I'm just going to say film because that's a shorter way of saying it. Your shutter speed is how fast you take the photo. So how fast photo is made. And this is counted in, you know, hundreds of seconds. It's very quick often. And your aperture is kind of like, it's like your window into your, it's like the window into your camera. So window into camera. And it affects sort of the amount of light that you're allowing in it. You can change the size of it and therefore allow more or less light into your camera. Just like by having putting a smaller window on a house. You can let less light in or putting a bigger window on your house. So you can put more light in and the aperture works essentially in the same way. So these three things together are going to work to make your exposure. So they all have to do with the amount of light that makes it to your film. And how that film then interacts with it. So in a way, you can also divide these into two groups. So you kind of have the light group is over here. This is, these are the things that you can affect that will, or these are the things that you will can do to sort of change the exposure. According to camera settings, your ISO is going to work in a little bit different of a way. A lot of times what you do when you're shooting is you set an ISO and then you adjust your aperture and your shutter speed and kind of just leave your ISO on its own. So I often, when I'm trying to imagine ISO, sort of separate it from the other two because although you can change it in your camera and you do sometimes change it, it's not something that you're changing as a active part of your photography often. It's something that sort of, as the light goes down and maybe a good example, you're photographing something right before sunset, as the sun is going down, you might be slowly, you know, moving your ISO up or if you walk into a room that's very different from the outside, you might just immediately put your ISO higher so you have better shutter speeds and things. But generally your ISO is something you kind of just leave. So I would kind of, as part of your way of imagining this, separate ISO and aperture. But we'll talk more in detail about all that. I just wanted to introduce these topics to you. I would go now and check out the other videos that we have about exposure, about ISO and shutter speed and aperture at alversity.org.