Lessons

Lesson Info

Overpowering the Ambient Light

Okay, we're going to start doing a demo. And so what we have here is remember, we have two exposures. I'm going to start dipping our toes into the pool and to do that, we have a model sarah coming out, I feel like I'm living like we love sarah. Come on out. We're going do sarah now service here we are going to be taking a bunch of pictures of you right now. And so what I want to do is make sure that we put into practice how tio control ambient light, how to control the light from our flash and do all kinds of things and so let's dip our toes into the pool. So what I want to do here and we've cleared out all of our students and john, we might need your help getting this tether cable out long a s o I'm gonna be doing is there's given I'm gonna be shooting and showing you that you can separate the ambient light from the light from the flash and problems that you might encounter, and we're going to rewind and go through those two exposure triangles that we talked about earlier and so what ...

we'll do first. Sarah come right over here we have and then also come forward just a little bit more come for a little more good good uh let's see if we could get rid of josh can you can move this little tether table and put it over here maybe josh is like becoming the assistant in that cool cool I don't know why I'm picking on you okay so what I also have done here is behind sarah we have lamps bunches of lamps and we have those on because when you're shooting inside or shooting at a location the's represent ambient light that we want to try to control and we have like from our flash to the first thing to do what I recommend is to start with the ambient light okay so I'm going to start there now what I want to do is I have my camera in aperture priority mod aperture priority mode and I'm going to put my eyes so all the way down to one hundred now this stuff that I'm showing you here it's going to work with pretty much any camera so let me first start by taking a picture and this is ambient light ok just an the light my shutter speed is really really slow so when we look at this we have a really wide open aperture that's going to pop up in a second we can see that we have just a nice exposure overall okay no flash no flash it all well, this actually is going to have some issues because we'll turn on our flash because sarah is so close to the background these two things they're going to be really, really difficult to separate and so to illustrate that we're gonna have you come over here I want to show you a different thing so come forward a little bit more behind sarah which will show you there are big panels of of lightness, big windows and stuff and sarah is much farther from those we're going to take a look at this ambient light okay, so we're just going to meet her this going to take a picture like that? Ok, now here, when this shows up we'll see that the ambient light is over exposed we have the light coming through the windows is too bright. Okay, so I could do is I could do lock on those some using my exposure locke take a picture here, take a picket look at this. When this pops up we're going to see that now the ambient light we have a nice exposure there sarah's underexposed and so I'm just showing you that's a show you that you can control the ambient light we have even started dealing with flash we have a subject over here so sir come on over here we're gonna have a really difficult time controlling the ambient light independent of the flash. So with the windows back there, I was able to expose the windows correctly under exposed. Now, watch this if I try to expose this correctly so I'm gonna go over here meter on this little flash use my flash exposure lock button that's the little star on your candid camera, take a picture. Now what we have is our lamp exposed correctly, and then sarah is going to be under exposed there's a little delay here. So now look at sarah is underexposed little bit. The lamp is exposed correctly, but we have a lot more difficulty trying to expose and change the exposure of this ambient light to me. Will of this and there's something else that's going on here, and that is that you're really close to this background. So when we turn the flash on it's going to be hard to separate how that lands, so we'll show you that there's just one of those things that, uh, if you try this at home and you're not getting the same results that I'm getting it's because you don't have you might not have enough distance. So let's, just try this, so, sarah, come on over here, we're gonna do this against this big window here. And this is where we going to start having some fun? Ok, so again, I just have my camera and aperture priority mode we're going to let it go exactly what it wants to do. I'm shooting at an aperture value of we're going to do after value of three point five from just picking out of nowhere, okay, this is on a t t l nothing is really happening there. I'm going to take a picture. This comes up, this will show up, we have over exposed background, we have correctly exposed sarah it's like that. Okay, now what I'm going to do is just very, very quickly I want to show you how you can under expose the background let's watch this on a canon camera there's this big dial right here or there's a button that says exposure compensation, you can push that, so I'm going to change my exposure compensation too negative too I want to take a picture. Ok, so we're gonna put these side by side when they pop up here. All I did was I changed my exposure compensation and you could see that the background is dark and there's also a camera back there, so this is a little bit brighter this is a little bit darker, so we were able to control that a little bit with our exposure compensation and depending on how bright the light is, we can control it a lot are just a little if we have in manual mode I could really control this and so I'm going to flip this over in manual mode and this afternoon after lunch when we get there, you'll see that why that's the case? So in manual mode what I'm going to do is I'm really going to change this, okay? So in manual mode, once this pops up, you'll see that this is even darker and watch this we're giving it a good, darker, even darker can you talk about maybe mark what you're changing? Yes, I want to show this and then I'm going to go through and show you each one so we're we're doing is I just want to show you this speed in the east so as we goes through, you can see that this is getting darker and darker and darker, so what I'm doing here is on a camera in fact I have a little worse my little clicker who still my clicker it's on the other table where it is c I accuse people who stole the clicker I have a slide for so here's what we're adjusting we have three things that we can adjust here this key no it's going to come up here so for the ambient light to make it darker brighter I'm using exposure compensation all I'm doing is I'm taking the exposure compensation on my camera and I'm rolling it up or down okay if I want to change the flash output I'm using the flash exposure compensation which we haven't got to now nikon owners I have this whole thing here this is don't be frustrated the reason I don't want to be frustrated is this doesn't work unlike on cameras, this doesn't work, so the reason it doesn't work on a nikon camera if you use exposure compensation, what will happen is everything will get darker or everything will get brighter okay, there isn't a separation between the ambient light and the light from the flash, so nikon owners don't get frustrated by this I want to show you how you can do that on a nikon into work just fine, but for now the stuff that I'm showing it doesn't really work on a nikon camera, so I know there's all these people out there like uh yeah, yeah it's pretty crazy so what I'm doing and I'll do it again I'm gonna take my aperture this time I'll put it down to you said it to eleven okay much smaller aperture, some controlling the ambient light much much more so I'll take a picture here my exposure compensation is at nothing it's zero ok, you could hear that really slow shutter and these air horribly composed by the way I'm trying to make sure I get ambient light so this is going to pop up here and when it does you'll see that we have this bright light so exposure compensation what I'll do is I'm going to roll that down by negative too so I'm saying take what you think is the right exposure stupid camera and under expose it by two stops it's only going to affect the ambient light ok, I'll explain what that is later that was my so I do that now watch what happens to this wall here when this next shot comes up you'll see this goes from the light great to a really dark gray so just rolling my exposure compensation I'm able to change that I want to show you something though that's different so sarah let's go over here to this side I'm putting my explosion conversation back to zero ok when I take my first picture here at zero they were all really, really slow exposure could have a really small aperture this will pop up we'll see that we have sarah in the background they're exposed you can see she's blurry, right? Why she blurry? We'll get to that because we're in the wrong mood okay, now when I change my exposure compensation what's gonna happen is not much because the exposure compensations going to change the ambient light because sarah is so close to the background, most of the light is coming from the flash. So what we'll do is we'll change our exposure compensation, and negative too. We'll take a picture here, okay? I think I bumped my focus button. Why did that? But what we're going to see is something significant and it's that duration, thinking that we talked about so notice in these this shot, and they put the next shot next to it knows this one is blurry, the first one, and this one is not, but they look the same. So what happened is when I changed my exposure compensation, I didn't change the exposure because sarah's too close to the background for that to matter, because the flash is eliminating her and the background. So when I say, hey, ambient light, be underexposed, the flashes still illuminating both, so it didn't change the exposure. I see students going on that makes sense, but what did change is the shutter speed became faster, and because this is being eliminated by the flash, the flashes a very short duration, and so it froze the motion, so we got rid of the blur, so this is where those two exposures become really confusing because you're like, what what's the hack because when I'm shooting this way I can control the background but when I shoot this way I can't and that's because of this relationship in fact I want to I want to add some bonus content can we do that? Yes we can so sara we're gonna have you is about and kelsey is going to bring a white board and a little cool piece of paper for me um we want to talk about something called the inverse square law uh converse gorilla so ok, I'm bad at math so kelsey brought this out on a piece of paper forming right? You have the newspaper free that's good you everybody should have a kelsey all right, so by the way, can I just say that earlier, audrey on twitter said mark, you may have missed your calling you could have been a pictionary champ with a drawing like that yeah, yeah also online people are talking about my shirt because evidently I don't have a polo shirt on so here's the thing I really own about six shirts that's I'm not kidding isn't it true? Yeah about six shirts and they all wore out right before creative live and so I had to like reach into the closet and find something that wasn't a polo shirt and this is what I got so that's why also if you go toe pocket wizards website the new plus three this is the same shirt I know, you know, like a backup edie. And here I am not in this year dole every guy ok, anyway, so inverse square law, right? So the inverse square law works like this. What it says is that light coming from a flash or anything? As soon as it comes out, it just drops really, really, really fast. And so I'm going to diagram this out. So the inverse square law says that light decreases inversely proportionate to the distance of its source. Don't quote me on that or that means is if I have a, uh sorry, this is a flash flash flash and I have a subject right here. There's a little line this is zero feet. This is one, feet two feet four feet eight feet sixteen feet. This isn't the scale, but you get it do we go away? Thirty to thirty two feet can let's pretend that this is to scale? Just go with me on this math people. Okay, so at one, feet one foot right here this is one hundred percent power very, very bright. Okay, now inverse square means that if we square too two times two is four and then we invert that two times two equals for we invert that we get one quarter so we go from one hundred percent down to twenty five percent is my math right hey failed math ok so we just lost from one foot to two feet we just lost seventy five percent of the power of the light so light when it comes out just goes only that like an eighth grader doing chores right just uh now I don't know I thought that ok when we get to this four squared is what sixteen okay that's a farce I'm going to use given to me from there okay sixteen one sixteenth which is what percentage six percent wow went from at two feet twenty five percent four feet six percent eight is what percent two percent in the rest of wining saying one percent were rounding these math people so you see what happens here is the flash goes from here down just sort of evens out it makes that noise too so the flash the farther you get from the flash the less power you have and it just sort of goes down and then sort of plateaus right here so what is happening is if I have my flash and I have a sarah right here or if I have a sarah right here the output of the flashes is pretty much the same in this realm of distance from the flash so if I have a wall right here the wall and this subject they're going to both be exposed about the same they're going to be about the same, which is what happened when we had sarah against this wall with the portrait is when the flash went off I can't really control the wall the ambient light exposure on the wall separate from the light on sarah because most of that's coming from the flash and it's about the same exposure as opposed to the other way, we had these big windows and say these air windows pictionary uh sara was up here, so what we're able to do is this light right here is much more powerful than the light coming in from flashback here, so I'm able to separate this and this is ambient light and this is like from the flash, so it's something you have to really be aware of when you're shooting a subject is how far away is your subject from something else behind it? If you want to control that because if they're close, you don't kneel to separate those two things you need some distance to separate. How are the questions on the universe square law in here are the questions is that are you going? Uh huh, yes, so that the point of it is if I am, I don't know if you guys get this if I'm if I'm a subject standing here in my wall is way back here many, many feet away my chances of being able to control the exposure here as opposed to that are pretty high, but as soon as I start going back here than the light falling here is from, my flash is going to be pretty much the same here and pretty much the same here, and so I'm not gonna be able to separate those two things. I'm not gonna be able to lock people out of a background or wall or a wedding bank, banquet or reception area, that kind of stuff, you need some kind of distance. So whoever said earlier, what controls flash exposure? And they said distance from flash to subject, and I said it doesn't it does in this case that's that's when that really applies british would like to know how much distance for separation well, here's the thing let's bring out sarah um we're gonna cheat, we have to do this off camera for this to work, but what what we'll do is I'm gonna put sarah really close. I mean, he was a different color see and sort of see this so you can understand how this works so it will do is we will take this flash misses the flash, we'll have sarah really close here, and you'll see that when she's really close that the light falls off rapidly even though the wall might be close to her so if I can get that flash and really close it'll fall off rapidly if I put sarah farther from the flash or I just moved to flash farther from sarah well see that is it's less difficult so the closer you get your flash to your subject the faster it's gonna fall off and the more you can control it let me show you okay better to see them to talk so watch this now unfortunately I might fry sarah's face my fried your face normally I do this with the flash off camera but we're going to see if we can do this with the flash of cameras so stand right here so notice sarah is pretty close to the wall I'll come back here I'm gonna be at a great distance a great distance from sarah made back here I don't know I did that actually, but I liked it. Okay? So we can see that in this example our our exposure on sarah in the wall essentially the same right and at the same distance what I'm going to do is I'm going to change my flash exposure compensation day I just changed it so it should give us mohr of the ambient light and mark would you say you're about ten feet so I'm going to say that I'm about ten feet away okay okay so notice that the exposure is the same but one of them because the shutter was so slow we got it was blurry the other one the exposure was the same it just wasn't blurry. Okay, now let's try this really close sorry from frying your face so I'm guessing that your face is gonna be over exposed because we're just so close okay don't worry he won't hurt your eyes it might he might hurt your eyes ok ok we're really close were about what? Hands with away from your face ok it's a really, really close is gonna pop up don't ever do this to somebody it's not really good okay, so it's weird now I'm going to take my exposure compensation down by quite a bit. I know don't you let me nicholas okay, now look at this watch this picture right here when it pops in see how much that just went down but I really had to get my flash close and so kelsey, can you bring on s t two out for me? So what we're doing is we're cheating. We're going gov ford by a little bit did john I'm gonna need you to help me to hold that so we haven't told you how to do this yet, but this is taking your flash off your camera and put it on slave mood so I'm going to put my flash on slave mode so I can shoot it off camera there we go, so just hold it like this really close just like this, okay, yeah, so I can get farther away from her from my camera, but I can leave my flash close that's the beauty of off camera flash so I can do that and you'll notice and here's one of those wonderful illustrations of how your flashes stupid a notice that we have this is much darker, but notice she is over exposed the reason she's overexposed because this is so sidel it remember our flashes dump details done, this is trying to average out to eighteen percent grade, so what it did was it said white and black should equal gray, which it doesn't. So what I'm going to do now, I'm going to control my flash exposure and to do that, I'm going to hit my flash exposure compensation button. So there's a button on canon cameras, it's flash exposure compensation on nikon cameras, it's there sometimes it's actually on your flash itself. Can you show that I cannot be awesome? I can't it's right here push that roll it up and down, so I'm gonna push it down can't see it in your word for it, so now this is down by two stops okay, this is again where manual mode is gonna be great and all kinds of different things that we hadn't gotten to you. Now look at this haha totally blown out. I use flash exposure compensation not blown out. This is really dark. Now watch this. So stay right where you are. I'm going to use my exposure compensation, which right now is underexposed I'm going to over expose it, it's moving that up mean up. This is going to give us a really slow shutter speed. The goal is I'm trying to brighten up this background. Okay? So here we go. Slows down there just a few freaky don't ever do this either. We just got a crazy cyclops picture, but okay, this is another great example of let's talk about what happened here. Let's, break this down. So I think we're good with the off camera flash stuff for now. So I'm gonna give you this. Take that flash. You need that. So let me break down. What? What happened on this second picture? So can we just put the second picture up full screen? We have to exposure triangles right way. Have two things wanted controls the flash exposure, which is going to be on sarah's face. And one exposes it was going to control this, but guess what we have? I don't know if you guys can show up here we still have these big windows here we still have ambient light. And so when I said I want to increase the light back here, guess what? When I allowed more of this light to come into the camera it's being illuminated by those windows. So when I said mohr, ambient light, well, there's more ambient light on sarah's face. So when I said, go ahead and let more in that is that her face is now brighter as well as the background, because that ambient light is illuminating both you and the background both at the same time. And so that's, where things go sideways, you're thinking, why did that happen? Why did we have first able to control this? And we had a good exposure. But as soon as we said more of this, it also messed up that because sarah and the background are being illuminated by ambient light, and so when we said more can come in, both of these things went up at the same time that make sense. So I don't know if people at home are tracking with this, I have to depend on you, so let me know if if that is, is that a way so can we ask you some questions please do because we have even mohr we're going to dive and even deeper, but I want to make sure we're we're on the same page so far as I would like to back up just a little bit okay? Because we've had a number of questions again about showing exposure compensation like on the back of the camera because you're talking about under exposing and overexposing and if you could explain that again, like when you say I am now overexposing yes, what that means and then which modes can you do? The exposure compensation in you've been in aperture priority is that correct? And a lot of folks are asking about manual as well, so that leads us into the next little portion because really, what we need to know is how does expose your compensation work? That's I think what people are saying is how does that work? Because exposure compensation works differently in aperture party mood going two dozen shutter priority mood and in manually it works differently and so what's happening. So what we're going to do, sarah have over there when I'm going to talk a little bit more about this and then we're gonna do mohr demos with this we're going again break it down piece by piece let's first talk about some things that ambient light and light from our flash have in common okay, so we'll look at these two things and I think some of the pictures that we just shot help it will be like oh, I got it okay, so number one s o we know that if we change the eyes so it will change how much light comes in both from the flash and from the amia light so this controls both the second thing is the aperture so by closing down the aperture we can restrict light that comes for from our flash we can restrict light that comes from the ambulance. Okay, so these two things will both impact our exposure. The shudder controls ambient light and the flash output controls a flash. So when I am an aperture priority mode what I'm doing is I'm sitting the aperture and the I s o and the shutter is being set for me by the camera and so when I say let's say this shutter is said it a hundredth of a second and I say when he's exposure compensation to make the ambient light darker this shutter is getting faster that's what's happening this is getting faster so all of the ambient light is going down and this is staying the same if I change the exposure to say mohr ambient light this is getting slower or light comes in and this all stays the same so back here when we had sarah close we could have shot her with no flash because we were shooting with an s o that was about one hundred and aperture that was pretty wide in a shutter that was really slow, and it was probably, I don't know, a few seconds and so the aperture, this ambient light was eliminating everything, and so you're not being able to separate this from this, because this is getting enough light to give us an exposure instead of this right here. So when we flipped around and we had those big windows, this was able to control the light from the windows and the flash, because it was so far away didn't have any impact on that, so we were able to separate these pretty easily. So I think that's we have, so we have to also go through those different modes. So before I move on, more questions are we're still tracking look, some question, yeah, there so many questions, markets it's overwhelming, isn't it? It's? Just trying to get a question. Okay, right. Let's, do this let's, let's, go well, let's, just start with where do you start? Okay. And just and lots of nikon lovers in the in the chat room and helping people are kelsey has said, can you clarify once more that you we will be showing this for nike honest way will be showing this with nikon and there's a reason I'm showing with cannon right now and it'll make sense when we get to the nikon stuff great yeah we will everything we're doing uh we will apply to both and sony in olympus and whatever you have it will work okay so where do we start let's do that so sarah come back on and come on back out come back on out I feel like I'm from the south comeback on out so where do we start so what I'd like to do is I want to dial in my ambient exposure first that's where you want to do on a dialling ambient light first on remember there's this important thing here and that is that the ambient light can be included or excluded you could included or excluded so what I'll do here on the reason we're shooting with cannon by the way not because it's your preferences because tethering works better in our situation there's a technical reason we're doing so I'm going to do everything with no flash to start with because what we want to do is let's let's start with one exposure triangle and then jump to the other one start with one and then jump to the other so on this just to show that we don't have any flash where's going take it off so uh sarah come right over here so sara close to the wall if we wanted change how much light is coming and going here, what I'm going to do first is so our live audience here do you want to include or exclude ambient light what's your choice excluded? Excellent okay, so what we're going to do is we're going to see if that's possible let's see if we you do it ok, so what I'm going to do is my eyes so is at one hundred lowering as low as I can to make it less sensitive to all this light bouncing around and then what I'm going to do is make sure that everything is set to just normal so I have my camera and aperture priority mode and I'm going tio put my camera at let's say f sixteen s that we really want to restrict the light came no flash gonna take a picture here? Well, that's really slow still going right really, really slow and so with that super slow shutter no way we have lots of ambient light pouring in so what we know is because of the exposure triangle I know I'm making all kinds of crazy pictures of you um we have to get our shutter speed fast, right? We have to get our shutter speed much, much faster and so what I'm going to do is use exposure compensation, ruling my dial you could do this on the nightgown as well exposure compensation to say go to stops under exposed by two stops okay, let's see what our camera does a fifth of a second is what we have so a fifth of a second and let's see did we make it? No. So what we're trying to do is exclude ambient light and what we've proven is letting the camera make the decisions for us in an auto mode aperture priority mode it doesn't work, it doesn't work, so what I can do is I can go to manual mode. Nikon owners love this because that's how you're going to do it. Okay, so in manual mood what we'll do is we'll start in the same place. So what was I was the aperture of eleven I think I'm like that. Okay, so I'm going to just roll my shoulder speed up so I knew it's gonna have nothing really fast and here's the picture not this is coming up it's just a total black square. So I started by eliminating the ambient light that's what we did, we eliminated the ambient light cause you want to control all the light using our flash now we know because of the inverse square law assumes I add the flash right here what's gonna happen it's gonna light up sarah and the background and so we're going to lose that ability to to fix that so we could do is take our flash offer camera, make it go from the side. We're not there yet, but let's, see what we can do with their flash and here's what's gonna happen? We'll see if we can show this that this game right here. So I'm in manual mode. I'm a f eleven at two thousandth of a second, what I'm gonna do is I'm gonna put my flash on the camera, turn it on assumes I do that it jumps down to two hundredth of a second because of sink speed, it just smacked into us. And so because of that, if I try to do this exact same picture with the flash, guess what? It's going to show up here? And we're going to get, uh, this exposure where this is a little bit dim, but we don't have that separation that we wanted, okay? Because of the limitations of the light that we have and that sing speed thing, this is something that we're not going to be able to separate the background from the foreground unless we learn about high speed sync, which we're going to a little bit later, I don't want to jump again, okay, so the basic the point of this is two separate sarah from the background right here knowing what we know now we can't do it doesn't matter if he was a candidate and icon we can't do it I know we can but we're not there yet ok let's try something else so coming this way this way we're going to try something else we have big, bright lights behind us again we're going to start with our our lights just back they're going to start an aperture priority mode okay, I am have my shutter it I mean my apertura f sixteen and I want to take a shot here and I have to change my focus mode sorry I ahead on hey servant you ok? So now uh what we want to do is you want again eliminate the the ambient light that they were trying to do we can't this right now we have too much light, I'll do exposure compensation negative too, but she'd already actually was on negative too. So right now we have we just can't eliminate that we'd have to jump to manual mode. So the reason I'm talking about going to manual mode over and over again because nikon owners you know, I said there are some things that won't work what we'll find is most of the time to make the exposure triangles work that we want to we're going to need to be in manual mode anyway and so maikon owners don't have to worry too much about it. Okay, so one of the things that we wanted to do is how do we over control this light since we have that barrier, right. So, sara, take a seat for just a second way. Have something called high speed sync and I think now it's time for us to talk about that because we keep hitting that to hundreds of ah, second barrier mark before we do. Yes, we clarify things. Okay, when you were just meeting with the window in your back? Um, love my joy. Love my joe laurie jo, were you meet a ring on on her, on the model or on the background? I was majoring on the background, and so because what I want to do is I want to start with the ambient light and figure out how to control that included or excluded. So I meet on the background and I tried to get that as low as possible. So that's that's, my preference is to always meet her ambient light first violent exactly where I wanted to be and then go from there. Okay. Yes. Another question from vinnie bear is, do you do you use the camera history graham to ensure that you have eliminated the ambient light or do you just go by the visual on the lcd um I don't know depends on what I'm shooting if it has to be something that's really really specific I might look the history ma'am but normally I just look at the uh the lcd and also I understand I just go with with my experience so I know if I shoot in a situation like this f sixteen and I'm shooting eight thousand of the second there's a new way the ambient light is going to get in there I don't have tio look at anything to know that it's it's kaput steve eighty six would like to know how do you know what flash powers start at we're starting we're just letting it t l in the word for letting the ninja flash thing figured out so I'm just letting it go so what we do is on flash exposure compensation we put it a zero which is you figured out we're going to trust you that's that's where we started and I think that some folks are still a little tricia saying a little confused about when you're using exposure compensation and when you're using flash compensation so so far I haven't used flash exposure compensation at all great yeah we haven't done that at all yet great yeah so I think what's happened is our experiences jumped over our knowledge yeah so I wantto go back a little bit and talk about high speed sync because I showed it and didn't explain it and we haven't talked about off camera flash. But I showed it and didn't explain it. So I've already done some stuff that we haven't gotten to yet so let's. First, figure out high speed sync. And then I can use it with reckless abandon. Never to go. Okay.