Two Exposures Explained: Ambient & Flash
What is going on here so it is imperative that you understand what is happening inside your camera and flash because the thing with the flash especially these guys the speed lights it can go sideways really fast it can really go sideways fast because there are so many different variables on things happening that again from shot to shot you see all these different things happening and sometimes you get stuff it's all blurry with a ghost floating through it like what is that? You know all that stuff so we need to know what exactly this flash is doing exactly what the cameras doing so we can control everything that's what we're gonna do so we need to start at one place and that is this when we add a flash any kind of a flash we had a flash to our camera on camera flash off camera flash the puppet flash flash of any kind anything that flashes one exposure becomes two exposures that is the key there are two different exposures there is the ambient light right that's the light that sort of f...
loating around out there that we can't control of the ambient light and then we have the light that is coming from our flash and we have to control those two things independent of each other and we can so we can say I want to have mohr ambient light less ambient light brighter background less background don't have more war flash less flash. I want the ambient light, you know, not only do we have two different exposures, we have two different qualities of light now to pay attention to so our ambient light can be hard, light and our light from our flash could be soft, light or the ambient light can be soft in the light from the flash could be harder, they can all be hard or all soft, and we get to choose all of those things. The important thing to understand is they're separate and we can control them independent of each other and that's, the fun that we're going to do. So let me give you an example of this. So I went to the park. Now, these pictures that I'm about to show you, I did this in about, I think, five or six minutes, something like that. So, uh, actually was sort of in a panic, so I knew I needed to show this. And so I called one of our models and said, please come to the park, we have about ten minutes to do this, and she showed up and we don't click click, click and he said things that were done and this is what we did, and so we can do that really, really fast. Okay so this first shot right here we have our ambient light is the same so look at the tree this is a big giveaway um so I mean I'm sorry the flash exposure is the same so you see on uh mrs lotion on her face is the same brightness right the same amount of light on both pictures but look at the tree in the background on this one on the on the rights are left side over here the tree is much brighter than it is on the right side okay see how you were able to change that and this really went like this click click click done about that fast so we can control those two things independent of each other and we can do the same thing with the light from our flash so check this out now look at the tree the tree is the same the same exact exposure but on the front we were able to change what our model of likes over here really dark underexposed not the appropriate my light on the right looks awesome right so we khun change those two things to john we need the white board here in a second so we're gonna talk about how we do that and an understanding of thie ambient light and the light from the flash and to do that I'm gonna draw something here it's gonna be awesome I'm gonna flip this around so I have the the white side. And do we have, like markers for this? That would be cool. Also, we have markers coming out here. I hope so. I'm gonna do in an excellent beach doodle. If not, I'll have to describe it to you. Imagine in your mind about how awesome it is, but we'll see. You know, it's, always one of those things we were doing a live show is like, all right, the actual market it's okay to have any other colors, or is this the only line? Okay, we have all we do. See there's. Kelsey. Kelsey, come out here. Kelsi and john need to come out here and say hi. So kelsey, you might remember from our last year of life she's, my producer and here's john cornyn cello he's gonna be helping out. So when I hear and matching air nice. Ok. Now you guys go family. Ok? All right. We're going now, okay, so I'm going to do the most excellent beach doodle. If you can find a red one that would be even more awesome than then just blew in. I'm so picky to you, is that? Oh, I need a white board and now I need stuff to write with and then it's oh, I need red and blue and green for a purpose mark it is I know that's the fun part of this workshop, by the way that I'm gonna love is there's so many different variables we're going to stop a lot and go what? Let's figure this out and we'll learn stuff, not with markers necessarily. This is awesome. I just needed this one. And this one. Thank you. Okay, it's my fault, by the way didn't tell them I needed different colors. Let's pretend by the way, we are at the beach. Okay, so this is water going down here. Jaws maybe, uh I can't drop in a way. That's just right. Maybe way don't need just, um, not the beach. We have a model with flowing hair flowing here, okay? And then we have a tripod with the camera on it with a flash on the camera, something like that. And then we have big headed person right here taking pictures. Okay, so what? We'll have let's pretend that we have a mme a big, bright sun, right here's, our big grayson and it's blasting a lot lasting like this is let's, say, toward the end of the day okay, by the way, guys from seattle that's, the sun and some big, bright thing that floats around out there it once in a while, eh? So this is going to be lighting up all this background right here. Now, if you take a picture normally with no flash, what will happen is the back of this person is going to be silhouetted, right? You're gonna have all this ambient light is gonna look great. And then this is gonna be a silhouette and it's not gonna look so awesome or you're going to have a picture where the person is exposed in the background is just totally washed out, right? Totally washed up. So we're going to try to do here is we're going to turn on a flash. I wouldn't turn this flash on pure and that flash what it does is it illuminates the front of the subject. Ok, so we have that's our two exposures, right? We have our flash right here that's the flash and then we have our light from the sun. This is ambient light right here. Okay, that's, what we have now, this ambient light, um, is something that is very interesting. So the ambient light let me just show this year on the screen, we have something that, um we have to react to the ambien light okay, this light right here and the reason because is that we can't always control it right? The sun we can't control there are clouds moving in and about things like that on because of clouds in the time of day ambient light has this tendency to change on us and so this light right here what we have to dio when we start we have to say, hey, mr camera let's figure out what we need to do with this stuff here to get a good exposure that's where we need to start when you say how do we get a good proper exposure with this? And then once we have that, then we can take our flash and adjusted so that we have something that seaver either brighter than the ambient light or balanced with that or just a little bit under but we have to stay start with this ambient light and make sure that it's good and so we're going to do that now we're going to start by looking at which is going to be a refresher for some people but stick with me on this because once we figured this out is going to apply directly to this and then we're going to start looking at how we can do do that balance between those two things and trust me you'll go right that's it okay? So um let's first start with this that we've all seen in our photography lessons before it's called the exposure triangle ok stay with me on this so we could take this will take the aperture shutter and I also will move those around so we have these three things and we need to understand what do these three things control now we really need to understand this because it's going to impact what happens with their flash later case number one the aperture controls quantity right quantity so it's looking at how much light is going through that amateur so quantity how much can the shutter opens and closes so it controls duration? So how long does that stuff go through? This is critical. Well, we've come to talking about balancing our ambient light with light from our flash critical, critical critical these two things understanding this is how much goes through and this is how long that stuff goes through. Okay, we're going to find out something really important here and then last the I s o controls sensitivity ok, this could this really impacts everything. So how sensitive are we too? All that kind of stuff? And so the way I think is the best understand s o is talking about my wife and myself, so if I'm at home in phoenix and it's one hundred two degrees outside which I think it is today inside our house we have the fan going we have air conditioning blasting and I'm usually it's like uh it's so hot right and inside our house it's maybe seventy five, seventy eight degrees, something like that I'm dying my wife diane is in the same exact place and she's freezing she has liked stuff on, she has a code on and so we have the same amount of temperature, same amount of heat or cool but I am more sensitive to it or she is more sensitive to the cool than I am. I'm more sensitive the heat so r r I s it was different I guess her eyes so is lower than my eyes, so I need more cool than she does ok? And our cameras were sort of the same so we could have the same amount of light but one camera response to that differently than another ok and that's true of both ambient and flash. So once we adjust s o it will adjust how the camera sees both at the same time. Okay, so we're going to do here is let's talk about this how does the camera figure out how much light toe let in and how does it balance those three things so somehow mysteriously when you put your camera on aperture priority motor shutter prior to mode or whatever it knows right. And even if you have a manual mode there's a little meter there that tells you what to set your dials and switches to and somehow it knows how to tell you what it is and so we might know what I'm going to show you this thing right here and is this the eighteen percent gray is one hundred percent wacky? Ok that's my motto eighteen percent gray is one percent wacky so what our camera does let me just let's show you with this is it has a little light meter inside there and it looks at all the different light in the scene all the darks all the bryce over here it would look at it you know this white stuff here in this gray and this stuff over here and it sort of puts it into a blender and blend it all r and averages all that it's a throws on the color away and averages those darks and brights and everything and it expects everything to mix to a middle gray which is eighteen percent great sort of like this background right here on this presentation that's what it expects and things can go really wacky because your camera is stupid ok your camera is really stupid I know I'm offending people but it's true your camera is not the brightest life in the drawer of the sharpest knife in the drawer right brightest light in the ceiling uh, it's, not any of those. So your camera is stupid and we have to help it out. I mean, it tries it really tries, but it's done. Okay, so what we're going to do is we're going to talk about this thing right here. This tt l'm me during this is why people love light meters because it's, they're not as dumb, they they're still done, but not as dumb as your camera and it's tl meandering and so tt l by the way, it stands for through the lens. That's what t t o is so light goes through the lens, it goes into our camera and guess what? Tt also stupid, stupid. He doesn't know it doesn't know what you wanted to do. You have to tell it to tell it what to do and so let me show you this little diagram here to sort of illustrate what's going on so through the lens works like this light comes in that's the yellow arrow. It travels through the lands. There it is, there's the mirrors inside this right here and these mirrors. What they do is this first one allows like to bounce up there's this thing right here inside the viewfinders called a penta prism that allows, like to bounce around trump and come out and that's how we see what the is coming to the linz right? The light goes through there and we can see stuff inside up here in this little area right here inside the pinto prison almost cameras that's where the light meter is that's where it is it's right up in there so as you're pointing the camera, moving it around it's, seeing everything you're seeing and it's saying ok, let's, mix everything up to that little gray and let's figure out how we should adjust our camera settings to get a proper exposure down here. Some of that light goes through this first mirror there's a little second mirror there that's your auto focus that's what that isthe ok, so here's the problem and here's where things happen with the flash that gets wacky and this is a preview we're going talk a lot about this here in a second when you take a picture those mirrors open and when they open, the light doesn't bounce around anymore, so this light meter doesn't see the light when your shutters the mirrors are up in the shutters up. So when your when your camera's shutter is open, light meter shuts down, I can't see anything that causes all kinds of problems with the flash, which we're going to talk this this this this is foreshadowing what that is okay, so what we're going to do is first, I'm going to demonstrate to you how dumb tl is and so to do that we're going to do this thing. We're gonna do a wall test. There it is. Ok, so I've got this little thing creative live guys put this together for me guys and gals. There's both here. They're awesome on dso john, if you could just give me this cameron awesome do that this's our cannon and I'm gonna do this with no flash, okay, no flash to start with was put that there, and if you're home, please try this. What you need is just a solid black wall or a solid white wall or a panel. Whatever it just has to be black has to be white. So what I'm doing here is I'm putting my camera on aperture priority mood. I'm gonna put it at let's see, I esso um let's do I s o four hundred some good? Yeah doesn't really matter. Okay? And then I'm gonna put my aperture at, uh, three point two doesn't really matter right? And I'm shutting off my auto focus because it won't be. It'll focus on this and I'm going to first take a picture of this white we'll hear someone to fill the frame and do that. So it makes your mind okay, I'm gonna look right here this white while taking a picture. Okay, now this hopefully will come up here on your screens and I'll show you guys here this is what gray it's absolutely great that white while they're there it is. So this white wall, his gray see stupid thinks that this is great because remember it's averaging everything out and thinks that this is great? I'm going to take a picture of this black right? So this fill the frame again, take a picture that ok? So the next picture that comes up, we know that it's black our camera is stupid, so there it is. They look identical. Isn't that weird? So can we show this side by side? We'll see if we can do some magic here and show them to side by side so we know one is white. One is black, but when we put these side by side and look at that, they're great. They're both great. So what's happening it's, that little blender thing that we talked about, where the light comes through the lens and the camera is averaging that stuff, and it's saying this should average out to eighteen percent gray and it tells the camera to set its aperture and shutter whatever to make it average out to great. Now watch this. I'll take a picture of both of these you the same time. Now, if I take a picture of both of these at the same time what you think is gonna happen, right? Because it will average them out, and black and white averaged out will be gray and so let's, take a peek and take a look, and I gotta focus it now, okay, so I had my auto focus off, so it should be a little bit blurry when this pops up. We'll see that something miraculous happens here it is it's, black and white out of focus, like I said, and notice that the white is a little bit gray will be under exposed so even that not so right. Okay, so the camera is doing its best, but it gets it wrong over and over and over again and that's what I say when I say your camera is stupid, what I'm saying is it's just doing its best based on how it was created to average things out the best it can to get this eighteen percent gray. And we know as photographer, especially wedding photographers know this when they're shooting brides in a white, you know, the white dress against a white wall if they don't do some exposure compensation or do some things they're going to have a great ride and guys and all their black tux is in a dark room if they don't do something, they're gonna have a bunch of great tux is, and so you have to use exposure, compensation and fix that, so our camera isn't so bright, we have to talk to our camera and say, I know that this is white and you think it's gray, so I'm gonna use exposure compensation and tell you that this is white and we can fix that now because we know that we can do that stuff gets what? That's, how we control our ambient light and our light from our flash. We're going to use exposure, compensation and do some things there's, some other things they're going to find out when you have a person sort of back a little ways with their flash, the cameras trying tio average the entire scene out, we're gonna get somebody that's, a totally blown off, you know, their head's gonna look like they explode all that stuff that's what's happening is their cameras trying to average all those things out, and it doesn't really work.