Reading Exposure via the Histogram | Transcription

As we through the Photography 101 series we’re going teaching you all sorts of ways that you can use the camera’s in-camera metering system to basically measure the amount of light around you. For right now we don’t want to get into all of the technical stuff, we want you to get out shooting with us and be able to understand what we’re doing in camera. What I want to do is teach you how to gauge your exposure using live view and using the live view histogram. The histogram is an incredibly powerful tool to help us to visually gauge the overall exposure in our images. We’re going to use this scene to kind of demonstrate.

Now what we have here is we have the sun directly in front of me right now. It is behind some clouds so it is softened up a little bit but it’s basically right behind a scene that I’m shooting into. This means that the scene is going to be back-lit. In the rocks, we have very deep and dark shadows. In the water, we have very bright highlights where the sun is touching. This is going to be kind of difficult when we get to exposing the scene correctly and the histogram is going to be a powerful tool. We don’t have that necessarily when we’re shooting with the sun. You can see kind of behind me as I’m shooting with the sun everything kind of falls to a very flat mid-tone range because it’s all being directly lit. I’m going to show you exactly how this would look like in a histogram but first let’s pull up our live view and show you exactly how we would do it.

I have my Cannon Rebel T5I right here on my tripod. We have the 55-250mm lens on it, this is just a standard kit lens. What we’re going to do is we’re going to shoot with a nice little composition giving us some foreground rocks and shooting these tidepool rocks and getting a little bit of the water splashing on them. The water is coming in from the right side so hopefully, we’ll get a nice shot as the water comes up and gives us some nice action shots. We have this mounted to our MeFOTO GlobeTrotter tripod. It’s a great tripod, inexpensive, and for what you get it’s pretty awesome. We’re going to mount it just so that everything stays stable as we’re demonstrating all of these different things and we can see exactly from frame to frame how it looks.

Let’s go ahead and hit the live view button right on our T5I here and it’s going to pull up our live view on the back of the screen. Right now I pretty much don’t see anything because it’s too dark, it’s underexposed completely. What we need to do is adjust the exposure so at least we see something on the back of the screen. Typically your live view is going to display something more along the lines of this. To get it to display the histogram we simply hit Info until the histogram actually is displayed.

Let’s go ahead and just adjust our shutter speed and our aperture. I’m going to go with, first of all, an aperture at maybe a little bit lower so I’m going to hold down the aperture button and we’re going to go down to maybe around F8. I do want a broad depth-of-field. I want to get around that optimal sharpness on the aperture as well. Now I’m going to slow down the shutter just so we have something to see on the screen. At this point I’m going to hit Info so we can bring up that live view histogram and there it is. The histogram looks a little bit confusing and it looks something like awful that we used to hate in mathematics with those curves and all that but it’s really not that hard to understand and it’s very simple when you know exactly what it’s showing you.

All the histogram is doing is showing you the overall brightness or the luminosity in your scene. What this means is that the left of the histogram, this little side over here on the left is going to be our shadows. In the middle we have our mid-tones, and in the right side we have our highlights. Anything that’s pushed into those areas basically is going to be demonstrated with these peaks. Wherever it peaks it’s telling you that a lot of the tonal range in the image is in that area in your shot. I’m going to show you exactly what that means because I’m sure that was very confusing to hear.

Right now we’re a little bit underexposed. Let me go ahead and keep underexposing and what you’re going to see is that once I get up to 1/4000ths of a second, everything is pushed to the left of the histogram. The histogram is showing that it’s underexposed. Everything pushed to the left means that we’re clipping our shadow detail. If we are losing shadow detail it means that it’s gone. It doesn’t matter if we’re shooting a raw or jpeg it is gone. When we get into post-production it’s going to print as pure black. Likewise, if I were to bring this all the way to the other side so now I’m slowing down the shutter speed going down to 1/100ths of a second. Now we push everything to the right side of the histogram. Everything is pushed to the right side. Our shadows come off the left edge so now we have very little shadows in the scene. We have a lot of highlights that are being blown out. Blown out is the same thing as clipping our shadows. We’re losing out detail in our highlights and that means those highlights are going to print as pure white.

The goal with the histogram is to get everything within the middle range. Basically what we’re going to do is I’m going to adjust my shutter speed and watch visually as the histogram pulls into the center. The goal is to get our shadows up against the left edge and the highlights up against the right edge without blowing out any highlights and without clipping any of our shadows. We get that right around, say, 1/250th of a second right now. We can get that right now because we’re not getting too harsh of sunlight, we’re covered in cloud cover but if it were much brighter, if there were no clouds then we’d have to go with a much higher shutter speed. That is a balanced histogram. Once I have that I’m just going to wait for my waves and I’m going to take my shot.

Noticing that we are at 1/250th of a second that means that we are going to be showing a little bit of the action in the waves. That motion, we’re not going to be fully freezing it. What I might want to do is just adjust my aperture down a little bit so I’m going to bring my aperture down to let’s say 7, actually we’ll go down to 6.3, we’ll bring the shutter speed up to 1/500ths of a second so we can freeze that water just a little bit better. Now all it’s going to come down to is waiting for that perfect wave and capturing our shot. By the way, I have locked in my focus. I just picked a point of focus that in the middle of our depth in that scene and I locked that focus right there so that way it doesn’t change throughout this entire scene and I did that just by switching this to manual mode. I have a couple good waves here coming through, I’m going to take a couple of these shots.

We have our shot here now what I want to do is demonstrate on an Icon it’s going to be a little bit different because some cameras are going to be different. Different brands, different makes, different models may or may not offer live view histogram but they will offer a histogram. I’m going to show you also what a different histogram might look like. Let me take a quick shot. I’m just going to take a shot over here of these rocks in the background. I want you to see what a histogram would look like where all of the tones fall into that mid-range area. Because the sun is basically front-lighting everything over here, that’s where all of our tones fall into.

Let’s go ahead and I’m going to swap these cameras out now. We’ve got the Nikon set up. I’ve got the same or similar composition on the Nikon set up as in the Cannon. Let’s go ahead and take a quick shot. Right now this is set to 1/500th of a second at F8 at ISO 100. I just want to see where we’re at with the exposure and we’ll adjust because we don’t have the live view histogram on the Nikon. We’re going to take that quick shot and this is the playback histogram. What we’re going to do is after we get the shot we hit play. It’s going to go to the playback menu. What you’re going to see is something more like this.

You’ll see basically the image by itself just like that. What we have to do is we have to hit up on the D-pad to be able to see more options. Actually, I think this is the default option right there. When you hit up again it’s going to take you to the second screen and it’s going to show you the histogram. We can see that our shadow are indeed a little bit pulled to the left too much. We can see that in the highlight, well we have a little bit more range in the highlights so we can pull those a little bit to the right. Let’s go ahead and make that adjustment again so what I’m going to do is I want to go up a little bit brighter. Let’s go ahead and adjust the aperture a little bit. I’m going to bring the aperture down to maybe around F5 or let’s go F6.3 and let’s take one more shot. Also the sun is starting to peak right now so we’ll see if that messes us up but what I can do is I’m going to give this a double check. We’re going to look at our highlight alert just to make sure. Yeah, we’re solid.

I’m going to show you guys the highlight alert in the next video so don’t worry about that, that’s going to be our second tool in getting the right exposure visually. Right now if I go ahead and go back to my preview we can see that we’ve maximized our histogram meter. There’s our final shot, we’re at 1/500th of a second, F6.3, ISO 100. We have our shadows pulled all the way to the left but they’re not clipped. Our highlights are pulled to the right. We’ve captured as much tonal detail in this shot as possible.

Quick Tip: I want to stop Pye for just a minute here. Throughout this video Pye has mentioned that the goal is to get everything in the histogram in the middle range. In other words, capture as much detail as possible and max out the dynamic range that can be captured by the camera. He’s right in capturing as much detail in that it’s a really great general goal most of the time but not all of the time. Let me show you a couple of examples.

Pye took this photograph for an equestrian fashion concept shoot not too long ago and if you look at the image and its histogram you’ll notice that a lot of the image is in the shadow range. There’s dark fur. The skin of the horse. The model’s outfit. The background of the barn owl. Everything is in the shadows except for the models face but guess what, that’s totally okay and it’s quite correct, it’s simply that the scene really is a naturally dark scene. Let’s take a look at another example and actually it’s from the same shoot. This time, with the model tying her laces on her boot. If you look at the histogram it looks like a lot of the information is pushed to the right side of the frame and it’s being blown out.

If I were to just look at that histogram and not the image I might guess that the image is actually over exposed but in reality it isn’t. It looks like it’s just where it should be. The point of this quick tip and exercise is to demonstrate that the histogram and the live view together are great tools and they’re a pairing so you should use them together. Always trying to maximize details in your histogram is a really good goal but make sure that the seat still looks correct as well because if your scene is naturally dark, well you’ve got to expect that your histogram is going to be pushed to the left a bit. If the scene is naturally bright then expect it to be pushed to the right a bit. This is where your artistic judgment is going to help you. It will help you arrive at the artistically correct exposure. Maybe not the technically correct one, but maybe the right one for that scene. Back to the video.

There is one benefit, in addition. A major benefit of a Nikon over the Cannon. We saw that the Cannon has live view histogram which is awesome. The Nikon didn’t which makes it a little bit more cumbersome, you don’t have that option to be able to adjust in live view, you have to go and take a shot before you can see the histogram. What the Nikon does have is is a center that can capture more dynamic range. We’re going to talk more about this and give you more demonstrations on dynamic range later and particularly shooting in raw. What that essentially means is that this camera can capture more shadows and more highlights within the same image when compared to something like this. This is has 14 stops, this has around 12 stops. Don’t worry this will make more sense later on just know that this captures more detail which is good.

Now I want to compare just that scene that you had going in this direction when we shot with the sunlight versus with the sunlight. I just want to show you what the difference in the histogram looks like. Here’s the histogram in the scene when we’re shooting against the sunlight. Whenever you’re shooting in a high contrast scene going against the light you’re going to have a lot of highlights and a lot of shadows. That means it’s going to be a U-shaped histogram because you’re going to have shadows in the left side and you’re going to have highlights in the right side and I think you guys are probably flip-flopped so shadows on this side and highlights on this side. You get this U-shaped histogram and we’re shooting with the sun I’m going to show you what that looks like so let’s go back over here. There’s our shot with the sun.

When we’re shooting with the sun we get kind of a different curve, we get this middle shaped curve where most of the tones are falling to this mid-range. That’s because we’re shooting with the light and it’s all flat light, we don’t have a lot of highlights, we don’t have a lot of mid-tones. When you’re shooting with the light it’s actually very easy to capture the entire dynamic range. The entire tonal range within one shot. When we’re shooting against the light, that’s when it becomes tricky, that’s when the histogram is going to be really one of your best friends in making sure that you get the perfect exposure.







Chapter 7: BONUS

Total Course Run Time: 6H 30M 21S