And so the aperture is the other device in the lens. This is the second most important reason that we're choosing a particular lens. First off, we're gonna choose it for its angle of view. And generally the second reason is because of its appetite. There's a few cases where we choose lenses because we need that specific aperture first. But in general, it's the second reason that we choose the lens. And in this section, we're gonna talk a little bit about aptitude range. Not very long, because this is kind of more photo. Wanna one stuff. We're going to spend quite a bit of time going through some of the more advanced in esoteric topics when it comes to aperture. So first off, just cover our basis with all of our new photographers. We don't want to be mean and jumped past them. I want to bring them along with us, talk quickly about the aperture range in a particular lands, and so each lands is gonna have an aperture that you can close down and set two different apertures. So a lens it go...
es to 1.4 is gonna have a very shallow depth of field in this illustration. Here, you can see those red hash marks over on the right hand side are illustrating the front edge of focus and the back edge of focus. So that is our depth of field between those two lines. As we stop our aperture down each time we get a little bit more depth of field with each subsequent setting, and this is the aperture unit you can see closing down in the middle of the lens, letting in a little bit less light that we're gonna need to compensate with on shutter speeds. So when we get down all the way to 22 in this particular example, that's as much depth of field as we can get. And you can see on the right hand side of the screen that we've got everything from 22 to the 33 mark in focus, but not stuff beyond it. So it extends greatly, but it does have limitations, and so that's the range. Different lenses are gonna have different numbers that maybe extend further in either direction. And so the visual that I keep in my mind and this is one of the most difficult things for newcomer photographers is 1.4 is a very small number, but it's a very big opening, and 22 is a big number. But it's a very small opening. In a case like this. Let's say we're at F 2.8 and we move to 2.0, we are opening up our appetite. It's kind of terminology we like to use, and in that case it's a full stop of light, which means it's double the amount of light when we go from 28 to 2 point. Oh, if we were to go the other direction from to Wait F four, which is the nest next number in the Siri's going from F four were stopping our aperture down, and we're letting in half assed much light. F four is the next number on our Siri's, and that is also a full stop, so a full stop can be more or less. You need more information as to which direction you're going, and so that's one of the things that we're doing in our cameras. There's more of this information in my fundamentals class. We're gonna pass by this pretty quickly because this is a slightly more advanced class. Now. Canon has three different lenses. We had somebody asking about these three different lenses. They make a 8 51 4 in a 51 to question for all of you here in the studio and at home. If each of these lenses is set to 2.8, will they have the same exposure and the same depth of field? Now? What's different is that we have a 1.2 lens, a 1.4 lens in a 1.8. But if they're set at 2.8, are they really setting it? Are they really letting in the same amount of light for the exposure and for the depth of field? And so I don't know how to address this question, but think about it. What is your answer? Yes or no? Let's just do an audience participation poll. Let me just raise your hand. If you think the answer is yes, it's the same and raise your hand. If you think it's no, they're different. Okay? The answer is they're the same, all right. And so one of the things that I was confused about was if I bought a faster lens. And this is a faster lands. No matter where I said it, it's always faster than everything else. Nope, You got to shoot it at 1.2. If you want to be faster when you have these three photographers using these three different lenses and they're set a 2.82 point eight is gonna be the same exposure in the same depth of field. Now, having said that, these are three very different lenses the size of the focusing ring, the construction, the bouquet, the out of focus area. All sorts of things were different. But if you're gonna be buying the faster lens, you're often buying it for the fact that it can shoot down at this 1.2 appetite.