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Exposure Triangle

At this point, you should all understand the basics of how the camera works, and we just showed you how to control each of the exposure related functions are aperture r shutter speed and r I s o now what we want to do in this video is give you all a re a world in algeria real, a demonstration on how the exploded triangle works, and mainly, basically how the aperture r shutter speed and I so work in conjunction to get to the right exposure. Now each of these things affect each other. Now what we have here is a little demonstration, and we have cups labeled sa one hundred two hundred four hundred and actually don't know if this is a real world analogy, because I know who does this in the real world, but it is going to be a good visual example of each of these components and how they relate to each other now before continuing. What I want to tell you all is when you think of these three components are shutter speed are ab attorney. So I want you to think of each of these pieces in the exp...

lorer triangle is having both an exposure related control and also an artistic related control. We're going to talk about that in this video, so let's start from the top with our shutter speed. Now remember from before if I pop this lens off of my cannon, which again do not give us a home, I can flip the mirror up and we can see the shutter door right underneath the mirror. Now the shutter is what controls the duration that light is going to be reaching the sensor. So the amount of time this congenitally measured in fractions of a second, so one, five hundred of a second one, two hundred of a second and so forth we can even go to the other side. We're measuring in whole seconds, so one second two seconds, ten seconds we can even go two minutes for what we refer to as shutter drags. We're trying to create really artistic long dragged out kind of effects in these images, so the artistic related component is basically and whether we choose to freeze motion or show motion, the faster the shutter speed at higher numbers, say one, five hundred one one thousandth of a second we're gonna be freezing the motion are images while the slower shutter speed on the centre drag side, I'm going to be showing the motion so that the artistic component of shutter speed now let's focus on the exposure component of shutter speed so we have our cups here is a one hundred, two hundred, four hundred we're going to get to the isos in just one minute. We'll talk about that in a second for now, let's use the ice in one hundred cup. But what I want you all to realize is that these three cups they represent the exact same desired exposure and to get to that exposure, we need to fill the cup with light, which in this case is going to be water and we need to get up to that top line on each of these cups. Okay? So let's, go ahead and grab our ice one hundred cut. I'm gonna get my phone out and we're going to just open up the faucet. So this is the amount of light that we have coming out is our water. All right? We're gonna time how long it takes to get to a proper exposure with this amount of light coming out. All right? So we're going to go ahead and use my phone and we're going to start to stop on this soon as we bring it under the water. Now you can see that the light is coming out at a fairly slow pace right now, so it's going to affect the duration, we're gonna have a longer duration here so to get the top we need roughly twelve seconds okay? So I'm gonna go ahead and just set this down now so that represents our shutter speed you can see right here so to get our is a one hundred cup to our desired exposure we needed the faucet to be open for twelve seconds that duration of time is our shutter speed and of course we're going to rounding these to the nearest hole number because well, this is not a very exact way of measuring let's move on now and discuss the after and to demonstrate that I have really cool and I wanted to show you all on modern lars were actually controlling the aperture digitally through the camera itself, but this is an old film manual aperture lens, and so we're actually controlling the after manual ate with an app to ring the actor is the eye or more specifically the pupil of our lens, which controlled the amount of light that reaches the sensor at any one point in time. Now here on my manual aperture linds, I'm set to f three point five this is the widest this aperture can get the most open and at this point we're going to be allowing in a maur like that if I were to stop it down so for example is I goto five point six thie after shrinks up a little bit a shrinks again at eleven f sixteen twenty to and thirty two each one of these stops down reduces the amount of light and you can see that as the aperture opening closes up now the numbering system for the aperture is a little bit counterintuitive after all with shutter speed in with so what we basically just double or half the number why did we have these weird numbers with the after and why is it basically getting smaller as we go higher up in the number well first you need to realize that the actor is actually a fractional measurement so it's not actually f three point five it's one over three point five and it's not for its one over four and it's one over eleven and you know that when you go up in fractions if that bottom number is larger you're actually having a smaller number there so f two is a larger opening than f four because that's one over to which is one half and one over four which is going to be smaller we'll talk about this in more detail as we keep going but that is the exposure function of the after controlling the amount of light coming in at one point in time what about the artistic component? Well the artistic component of the after is in controlling the depth of field the low earthy after number so I go back down to f three point five we're essentially decreasing our depth of field now what this means is that anything that's behind the area that we're focusing is going to get blurred out or it'll fall into ok as we refer to so that's that kind of pleasing background aesthetic of the blurred out area that's out of focus as we stop down the after to these higher numbers so f twenty two and f thirty two then we're increasing the debt the field of so we get mohr area in our image in focus so that's basically the artistic side of controlling the aperture all right, so let's get back to our faucet analogy now what would the after being our faucet? Well, the actor is essentially that inside component that controls the amount of water coming out so as we bring the fossa handle up, that opening is larger this would represent a large after say f to r two point eight and this is the maximum amount of light that we can allow through. All right, so this is our widest open after now as I stop it down that opening allowing the water through is starting to closed down we're allowing less and less life through and we get down to no light so that's our after in our faucet now let's, go ahead and go back to art I saw one hundred cup I'm gonna dump this out and what we're gonna do is we're gonna open up our after or open the faucet all the way, and we're going to see how that affects our shutter speed because the first time we did this, we didn't have the faucet open all the way. So let's, go back to our little timer right here. I'm gonna open this all the way. We have the max amount of light coming through let's. Go ahead and measure the amount of time it takes. Now, in his start, he could see it feeling much faster to our desired exposure and right there. Okay, okay. So to get to the same desired exposure with the sink open all the way now we only need a six second shutter duration. So it looks like we actually allowed double the amount of water in by opening the faucet up all the way. This would represent one stop brighter in your aperture. And we're going to talk about stops in just a second. It's just a simple term, but just know that we double the amount of water coming through, which allowed us to cut the shutter speed in half to six seconds. Okay, so that is our exploded component of our aperture, and we now need to jump into it, so now the iso represents a measurement of the sensitivity of light of our sensor if we're talking about a digital camera or of our film, if we're talking about film cameras, but what does that exactly mean? Well, essentially, what we're saying is that if you increased the sensitivity of the sensor itself to life and that means you need less light to get to the exact same exposure and that's what we have here remember when we talked about this first, we said that each of these cups represented the exact same desired exposure that's because isil one hundred, we need this much water, and this happens to be a thirty two ounce cup, so we need thirty two ounces of water to get to that correct exposure or thirty two ounces of light that really does makes sense, but that's, how much light we need now? So two hundred were at double the sensitivity of is a one hundred, so we need half the amount of light. So this case we would only need sixteen ounces of water or sixteen ounces of light to get to the same desired exposure at s o four hundred again, we've doubled the sensitivity from is over two hundred so now we need half of so two hundred amount of water to get to the exact same desired exposure er that is the exposure side of isobel what about the artistic side? Okay, so the artistic side is a little bit different when we talk about s o because any step up that you go on s o is going to reduce overall image quality essentially a step up to two hundred or so four hundred or a hundred. Each step up is going to reduce overall dynamic range is going to reduce color it's gonna introduce grain and noise which will kill your detail and so forth. So in general, I would say that the goal is going to be to maximize the quality of your images. And so you might be thinking, well, if I want to achieve that filmic look, why not go outside the middle of the day and shoot so sixteen hundred? Just so I have some grain and have less color. And so it looks more filming. Well, there's a problem with that we can actually create filmic looks in postproduction fairly easily. But the problem is that if you go out and you shoot at sixteen hundred middle of the day well, that's, the way the image is there going to be it's only going to be at that quality level. Regardless you can't ever go back and undo that so if we shoot that way strictly for the purpose of getting that film look that if we ever wanted those images to essentially be that full quality and the full sharpness and have the best color and so forth we wouldn't be able to go back and make that adjustment whereas if we always shoot at the lowest possible native are the lowest possible so we can always go in in postproduction and we can add noise and grain to create those film it looks that we want so save those types of things for postproduction what I would say is as a general rule shoe at the lowest possible so to get your desired exposure or to get the settings that you need in camera to get the exposure you want and then make any other changes in post production to get those kind of filmic effects and so forth now let's go back to our analogy here what we're going to do is just open up the faucet all the way I want to demonstrate basically how these different iso settings are going to affect our overall exposure in our shutter speed okay, so let's go ahead and dump this cup out we're going to open up the aperture of our faucet all the way so we're allowing in the maximum amount of light which in this case is water let's get our little phone here and we're going to start measuring okay, so we had six second before I'm gonna double check to make sure that right so go ahead and we're going to start we should get to about six seconds to get to a proper exposure with our one hundred okay, I went a little bit over we're at six point seven seconds close enough so we're going to say six seconds is going to be our correct shutter speed to get our is a one hundred cup full to our desired exposure let's check out the two hundred cups and now we only need half the amount of life so we shouldn't need three seconds defeat start let's see and stuff look at that I just want to show this to you can you see that? Three point zero six seconds exactly half the shutter speed of one hundred ok let's go ahead to our eyes up for now we need half the amount of light from two hundred so there should be one point five seconds. So start stop. So our final time with our eyes a foreigner cup with one point to a second probably hit the stop on a little bit too quick for the sake of argument were going to say one point five seconds so I'm gonna go ahead and close our faucet or rapture now what you saw here was that the iso sensitivity allowed us to manipulate the shutter speed and in this situation we're manipulating shutter speed but in other situations you might use it to manipulate the aperture it doesn't matter but let's say, for example that this was a case of we're shooting say a runner or an athlete and as we're shooting that athlete, we notice that we're one one hundred a second for a shutter speed but at one one hundredth of a second we're not freezing the motion enough so the runners just a little bit too blurry, so what we need to do is double the shutter speed, but let's say for example, that are aperture is fixed at two point eight we can't go any wider because the lens one allows two so this is the maximum amount of light we can get in the lens where I saw one hundred at this point, the only option we have is to increase the iso speed to increase the sensitivity from one hundred, two hundred or one hundred four hundred of course each of these steps up is going to redo quality, but it allows us to increase the shutter speed to get a usable image. After all of your shutter speeds too slow to even get something sharper to get the desired kind of compositional effect, then it doesn't matter what kind of dynamic range you have it doesn't matter the sharpness nothing else matters so is so is kind of that last resort option at least that's the way that I use it, I just my aperture in my shutter speed for my composition and then all I just my eyes. So if I can't get to the correct exposure with those two adjustments by itself, otherwise I leave it I saw one hundred all the time. Okay, so final recap, our shutter speed is controlling the duration of time light is reaching a sensor thie after is controlling the amount of light reaching the sensor, and the iso sensitivity is controlling wealthy overall sensitivity or the amount of light required from the sensor to get to your desired exposure. Now it's assignment time and what I want you all to do is practice everything all the concepts that we've learned here it's exposure triangle example except don't do it in front your sink don't go get measuring cups and said you already know how to adjust your shutter speed your aperture and your eyes so manually on your camera. So go out in manual mode and I want you to play around with these three settings. Notice how basically adjusted your shutter speed is not only just the overall exposure, but also effect, whether you're capturing and showing motion or whether you're freezing motion notice how when you adjust your aperture you're not only adjusting exposure, but you're also adjusting the depth of field in your scene. And then, basically, when you are in situations where you can't get to the right shutter speed or the right after setting and get the desired exposure, we'll tweak your sensitivity to get you there. That's it for this video, and I'll see you on the next one.