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Exposure Values

Okay, folks. It is time to get to exposure values. And when we talk about exposure values what we are talking about is shutter speeds, apertures, ISO's, and we've talked about all of these isolated, individually, so that we understand, "Okay, we got this one right, and we got this one right, and this one right", but now when you start mixin' 'em in the party together, there's gonna be some interesting interactions, and there's gonna be some trade offs that we're gonna have to make in here. I'm listing 'em this way because if you think about it, we have our aperture, and our shutter speeds that we're gonna be setting. We have different lengths and then we have the ISO which is controlling the sensitivity on the sensor, and this is very much the way it appears right in the camera. The light comes in the camera, it goes to the aperture, we open up a shutter speed for a particular length of time, and then the sensor records it with the ISO setting that we have. These are the numbers that w...

e're gonna be looking at and working with. And you have to be thinkin' about what is the best set of numbers for a given situation? Fact of the matter is, is that there's a lot of numbers. And I'm only showing you one-third of the numbers, 'cause you have all those little third increments in there as well. And some people just get a little bit stymied, there's just a lot of choices, I tend to like pictures at this shutter speed or this aperture, and you know this is not a lottery game folks, you aren't supposed to be choosing random numbers here, you're supposed to be choosing logic as you want to choose one or the other so, we're gonna get in, and really understand what our priorities are and where we want to set our camera for a variety of situations. The first thing that you really need to ask yourself, for a lot of reasons, what are you photographing? What is the subject of your photograph? And when it comes to these exposure values, what is really important is your subject moving, okay? Pretty easy question. If it is moving, one of the options you have is to freeze the motion, or you can go the other direction and you can blur the motion, alright? Now, if it's not moving, well you have a couple options down here. You have maximizing the depth of field so everything is in focus, or you can go with really shallow depth of field. And we do actually have one more. If you remember in the middle of our aperture range, is where we're getting the sharpest results from our lens, so we can also use that as one of the options. And the world of photography is really broken up into these five options here, these treatments or styles of photographs. And you can look at any photograph and just kinda pick out which one it is. Freezing motion is a faster shutter speed. Blurring motion is a slower one. Aperture is either fast, or you know, closing down the aperture, middle aperture, or wide open. So it's all gonna fit into these categories. So let's walk through a number of different scenarios and figure out what I was doing in this particular photograph. So, eagle coming into the river ready to grab a fish out of it, well, we're gonna try to freeze that motion. Alright, so let's take a look at our exposure settings, we're gonna have aperture, shutter speed, and ISO in this case. So, first thing on my mind, and I always kinda, this is kinda the default first standard, and that is I wanna get the best information off my sensor possible. And so I leave my camera set to ISO 100, virtually all the time, when it's not in use. And then when I actually start using it, I adjust it according to it's need, but just as a default I wanna have it at the best ISO setting possible. Now, we're going to need, I'm gonna need some help on this and so, this is not a quiz but for now I want Team A to help me out. So Captain get the microphone, and teammates be ready to whisper in additional information. So it's not quizzes but I just need some help. And so, what do you think Team A, do you think I should be doing here next? What are we trying to do? So give some recommendations as a photographer, what do I need to do with my camera? (whispers) So look at the shutter speed first. Okay, do you have any suggestions for shutter speeds? Just call out some numbers, what do you think? 2,000. 2,000th of a second. That sounds like a really good shutter speed for something like this, 'cause it's really fast action, there's some water involved in there, and that's gonna be a good place to be shooting a photograph like this. Now, when it comes to the aperture, let's just deal with what we would ideally like. And what aperture would we want to be shooting in this case if we could shoot with anything we want? One of the questions I would ask is, "What is going on in the background, and is that something I wanna have in focus or not?" Now in this case, it's safe to say that there's not much going on in the background that holds any interest in this photograph, so it's probably better to have it out of focus. Let's just focus in on our subject. And in order to get a shallow depth of field, where do we go on our aperture? We're gonna go four, because it's gonna let in the most amount of light, but it's gonna give us the shallowest depth of field. Kind of in an ideal scenario, this is where I would like to shoot this photo, alright? Let's take a look at the light meter. Light meter says, I am three stomps underexposed, okay, that means it's gonna be dark. Now I need to fix this problem, let's work this out here. Can I fix the problem with the aperture? Can I change the aperture to let in more light? Nope, it's already maxed out right there. Can I change my shutter speed? In theory yes, but then it kinda defeats what I'm trying to do in this particular photograph. And that's not a real good option, so ISO, this is where some people might have taken me a little too literally when I like to keep the ISO at 100. I like it there, but I'll change it if necessary. And this is the necessary part. I want to keep the shutter speed there that's more important, and I'm gonna change my ISO up three stops, because that's how many stops off I was here. Now, this is the correct exposure for this photograph. Would it be a smart strategy just to keep your ISO in auto and set the other two? That way if the bird happened to fly into a situation with more light or the scenery was a little different, you would capture more? It's possible, but it depends on how dynamic the situation is, and what you don't know about this is that this was actually a very easy shot to get, there were seven eagles up in the tree and they were just taking turns coming down one after another, and so it was like a 'fish-catching' or a 'bird catching fish out of a river' or something? (laughs) I had a bit of time to kinda get that in a more fluctuating situation, auto-ISO might be a little bit quicker way of doing it. But we're manually wanting to step through these things here. Okay, Team B give me some help out on this one. So, I got a pretty little scene up in New England-area here, and I want to blur the motion of the river here. Let's just assume ISO-100, and I think I know what you're gonna say, but make it more specific, give me some numbers. I want a number. (whispers) We'll go with one second on that shutter? One second, you want to go one second because we're trying to blur the water. And I told you earlier, that I like my photos at one second. Alright, so you're cheating, you've been listening to me. (laughs) So one second would be good. Now, depth of field-wise, well this is kinda pretty back here, so maybe we'll want to have a little bit of that in focus. It's actually not that far away from the river with this perspective and how far we are back here. In this case, we don't need at 1.4, because we're not gonna get shallow depth of field, and so we'll take a little bit of depth of field in this case, F8 would probably be fine and hold enough depth of field, there's also a really, really sharp place on our lens, so that would be a good place to be. This is making me feel good, I like, I like this. Let's take a look at the light meter. Light meter in this case says, we are two steps overexposed. This is actually a rare problem in photography, too much light. It's a problem like having too much money, it's a nice problem to have, okay? Any suggestions on what Team B might have for me on too much light. What should I do? (whispers) We're actually now gonna stop down on that aperture. And so your suggestion is? 16, because that's two stops of light? Right, you can see on the light meter we're two stops away, and this two equals over here on the aperture when we go from 8, 11, to 16. That is the correct solution there because having a little bit more depth of field, that doesn't really hurt anything at all. Now we're going from 8 to 16, and there's at least three people out on the internet that are going, "Oh no, defraction!", but that's not really a problem at all, that's really not gonna be a major here at all in any way. We get our primo ISO, we get the shutter speed that we wanted, and we get a darn good aperture that I think is going to work out very well for this photograph. Very good, nice job. Alright, let's go back to Team A, give us some help out with this photograph here. This was in Tanzania, this is where we're going on safari, here. I can't wait to get back there. One of my favorite photos from that trip. Alright, we know we're gonna be at ISO 100, and in this picture I'm trying to maximize the depth of field. I've got zebras in the foreground, midground, background, in the far background too, and I want them all in focus. So I don't just want a word, I want some numbers. Give me a number. (whispers) F22. F22. Alright, there's those three people out on the internet, that are just squirming in their seat, because they're getting their defraction. But no, if you want foreground to background, 22 is gonna get there. Ooh, now, what about shutter speed? Because you know I'm not on a tripod, you gotta be in those Land Rover vehicles and stuff, and those zebras, those aren't stuff, they're there and they're wagging their tails. They might not be running, but they're all moving around a little bit. What sort of shutter speed do you think I should have my camera at in this sort of situation? You gonna throw out a recommendation for us? (whispers) Are you screamin' at your computers at home? Scream it really loud, I might hear it. 125. 125, why do you say 125? Oh they didn't know I was gonna ask why. (laughter) Well I'll tell 'em why, because generally for handholding you need a 60th of a second, and as you probably watched in the video, I like to have one extra just for safety, just a little bit of caution. When you're standing in front of the bear, just one step back of everybody else, you know? A little bit of caution there. Most people are gonna be able to really get sharp pictures at 125th of a second, and you can tell this isn't like a super telephoto lens or anything. That's nice, let's take a look at the light meter. Light meter says, "Uh oh," okay? Not a big problem but a little problem here. This picture's gonna come out two stops underexposed. Any suggestions, what you would recommend for me to do with the camera to adjust for this exposure problem? Sorry, were you or were you not using a tripod? Was not. I was in a Land Rover and, those things were movin' around. Good question though, are you on a tripod? Bump up the ISO to 400. Bump up the ISO to 400? That'd be a good call. I actually did a little bit of both. I went up to 60, and I went up to 200, so it's a six-to-one, half a dozen the other-type call in that case. In this case I went down to 60, because there was only one other person and he wasn't movin' around too much, so I was able to feel confident in shooting at a 60th of a second. So that's kinda the judgment call you get to make onsite. But that is exactly the right thinking that you have. Alright, let's send it over to Team B, and help me out in shooting a portrait here. Let's get our numbers up here. Tell me what you think we should do first here after we get our ISO set to 100. Let's get that microphone to the captain, and get some feedback from your team. We'd like to set the aperture to 2.8. Alright, that's a good call. Wanna get our subject our in focus, and not worry about sort of things in the background. Now real quickly, what sort of shutter speed do you think I should be using in here? Any things that you'd kinda like? We kinda feel like 60 would be a good place? Okay. What you may not know, and may not be real clear. You're goin' in the right direction. I woulda been happier, a little happier, if you had said 125. But what you didn't know was I was using about a 200mm lens. I might want something a little bit faster, in this case having that little bit faster shutter speed is probably a smart choice here. Let's go ahead and take a look at the light meter. Okay, this is like nothin' this is just one stop. Well, we can't change our aperture to let in any more light what do you think we should do to accommodate this little underexposure problem we're having right now? Well since you already talked about not wanting a slower shutter speed, let's bump up the ISO to 200. Bump up the ISO to 200, nice call. Good job on that, very good. Too bad I wasn't givin' out points on that one. (laughter) Yeah, that's exactly right, it's these just subtle little judgment calls, and what you're doin', you've probably heard the philosophy of 'pick your battles'? You're pickin' the things that are important to you, and you're compromising on the things that are less important in a photograph. Okay, another one of my favorite pictures from Tanzania here, it's just a tree, it's a forest, right? Alright, so we want to maximize sharpness, we don't need a lot of depth of field, there's not a lot of movement in here, and I think you guys are gonna be pretty smart, so I'm just run through this one myself. Where's the sharpest aperture on any particular lens? It's in the middle of the range, so in this case it's gonna be 8 or 11. Now, I'm not on a tripod, and so I need to be aware of my handholding movement, 16th of a second is probably fine, let's gonna do one extra for safety. So that's 125th of a second. That seems all pretty good. Take a look at the light meter and holy smokes, I got a lotta light here! Got a lotta money! Where am I gonna spend all my money now? This is pretty easy. In this case, I don't need the depth of field, and using a faster shutter speed has no downside at all, so let's just use that faster shutter speed, and that's a great use of those faster shutter speeds in this particular case. That's how we solve that problem. So everything that I know of, basically fits into one of those five categories. And you've all done a really good job figuring out the philosophy of how to do that. Now you might be saying, "Oh, that's a lot to think about in a really quick bit of time." Yeah, at first, but once you get used to shooting, this happens really quickly. Good photographers will go through this relative whole process in seconds in their brain. "Oh I know I need this, I need this, and that leaves me with this." And you're right there where you need to be. But there are some tricky situations, so I wanna take you through a couple of trickier situations. Alright. So we have an image here and there's something unusual going on in this image. See if you can figure out what it is, and I'm gonna ask you to figure it out in your own brain. There's something different about this photo than the photos we've seen before, and it's gonna come into play when we try to take this photo. Now, they're moving a bit, but they're not moving terribly fast here. It's somewhere between stopping motion and just maximum sharpness in this case. So I'm gonna set ISO 100 and as I said, they're not moving really quick so your normal handholding 125th of a second should probably be fine. I'm shooting off of a bridge down into a river, so I don't have a lot depth that I need to worry about. It's just kind of that F8, 'be-there' type philosophy, it's a nice middle aperture. I take a look at the light meter, and okay now I don't think you've seen this one before, but that's three stops underexposed, the red indicates I am more than three stops, I could be four, five, six, seven or a hundred stops off. It's just letting us know that we're off there. And so now I need to start letting in some more light, and I need to start compromising on what I really want it to have. A first step for me might be to back off a little bit on the F8, let's just come back to 5.6, that's probably fine. I'll go to F4 if necessary but let's just back off a little bit there. My camera is really clean at ISO 800, that's gonna solve the rest of those three stops. I can shoot this picture at those settings and I'm happy with that, it's a good combo I think. But when I actually shoot the photograph, at these settings, here's what happens. Okay? Can anyone here explain what happened? Why did I get this result with those settings that I just made? Raise your hand and we'll pass the microphone. Yes. The camera was trying to get 18% gray, and it made that black into gray. Right, yeah, exactly right. The river was very, very dark, the camera didn't know the river was dark and it just assumes everything is that middle-tone gray, so it brightened it up to this. What I need to do now, is I need to push this down darker and I need to make it darker. And that means I need to go over here and make it darker by one of my settings. And there's a lot of different ways that you can do this. What was the last thing that I bumped up? The ISO. Maybe just bump it back down with the ISO. In this case I need to go down about two stops to get it back down to ISO 200, which improves the quality and gets it the right tonality as well. Be aware of those situations that are much darker than average. Okay, this one I think you'll pick up on pretty quickly. This is kinda just the opposite that we talked about. This picture is predominantly white, this lightness is going to throw off the meter when we finally get to that. In this case, I really wanted that long shutter speed in this case, because I wanted that really blurry water so I wanted to get 30 seconds in there. I don't have a lot of depth of field, in here, it's just this kinda one rock, so F8, their middle of the range'll be fine with me. Take a look at the light meter, I'm three stops overexposed here. In this situation it's pretty easy, a little bit more depth of field isn't gonna hurt me. I prefer not to be down at F22, but in order for me to get to 30 seconds, which is the primary directive of this shot, that's where I ended up being. Now when I actually take the photo, it comes out darker than expected, the camera's not used to all this bright light, it wants to make it darker. So now I need to go back in and brighten it back up. And I'll do that by just bringing that aperture back from F22 to F16, which gets me a little less defraction there and gets those three people on the internet feelin' a little better about my photography, 'cause there's less defraction going on. This picture is supposed to be in the plus side, around plus one. Hopefully that takes us to about all the different scenarios.