Changing Background Color with Gels: OnSet ep. 252

Changing Background Color with Gels: OnSet ep. 252

February 28, 2020 27 By Peter Engel


Hey this is Daniel Norton, and I’m here in my studio in New York City with Farrah. Hi! And we’re gonna make some kind of fun shots today. So a lot of times when we’re doing live demos I, you know, get a request to make the background a different color and we like to have fun with gels and change that up, but then after I get a lot more technical questions like “how exactly did you do that?”. Because you know we’re usually just, kind of, doing it quickly and really if you want to do a color change in the background with gels there is a science to it. So we’re gonna talk a little bit about that today, talk about exposure and talk about like things and how to put it together. So what we’re gonna do first is, I’ve got Farrah, she’s got this beautiful yellow dress, I guess is more of a shirt, outfit we’ll call it. and I’m gonna go blue on the background because a blue and yellow kind of work together, right? And one of the keys here is that we want to keep our main light, our key light, on Farrah or any of the light that’s going to hit Farrah. Any of the light that’s not the background light needs to not hit the background. That is super important because any light that hits the background that’s not blue, is going to make the blue less saturated. So for a key light I’m gonna use this 3-foot octagon. this is equipped with a grid, the grid is gonna narrow the beam so it’s going to make it so that the the light, doesn’t hit the background. Simple as that, right? So let me show you how to do the background. Okay, so I’ve got two B flats, you could see that, and bouncing into them I have this Profoto B2, you know, one on each side. I’ve fitted them with the blue gels that I want to use, they’re both the same gel of course. And in order to get the background even I made them, basically even from each other. Everything set the same. Now the first thing I’m gonna do is, I’m gonna set my background to basically be the exposure that I want to shoot at which is f/4. So I’m just gonna fire my lights. f/4, right? Now we have the lights exactly where we want for their on exposure. An important thing to remember here is that, when you’re doing gels here, don’t worry about the exact exposure, don’t worry that it’s f/4. Know that right now it’s set “on exposure”. Okay so come on to your spot here. So what we’re gonna do now is, we’re going to basically just get the background set. Again I’m shooting at f/4, 100 ISO. I only have those lights going off right now, even though I have my key light over there, I just have the background lights set, because I want to do that separately, right? so what I decided to do when we set this up was, I saw how ,kind of, it was cool. This cool balance with like the black of the V flats. Facing me. So I’m actually gonna, kind of, make a fun composition that way shooting horizontally but let’s just see what the background looks like. Again this is “on exposure”. So we can see that it’s a nice bright blue, right? but we are getting a little bit of bleed through here. it’s not really flaring forward, but we’re getting a tiny bit. In fact we know that it’s actually bright because we’re getting, even, some light here in the front of her face that just bounced, right? So we know that background is too bright. No matter how we metered it, no matter how much the science of it says “oh the meter read it”, it’s not right, I know it’s not right to what I want. So what I’m gonna do is turn that light down. I actually kind of want a deeper saturation anyway, so I’m gonna go a full stop. You can basically do it to taste, but you definitely want to do it enough that you’re not gonna get any of that light in the front of her face. So let’s see, again we’re doing another silhouette shot here. We’re just establishing. There we go, now we’re closer, right? You see how nice the hair is. We’re not really getting anything there. I mean if I was to grab my exposure slider, obviously we’ll start to get some, it’s not like a deep dark shadow, but you know it’s down, it’s stopped down or so. So now I think that’s actually probably okay, but I do think the blues brighter than I wanted it to be for this yellow outfit. You know if she was wearing, like, a bright, shiny, yellow outfit that might be good, but she’s got, kind of, a darker yellow, so I’m gonna go down one more stop. Okay I like that. So let’s start there, right? So now, again, what’s the f-stop for the background? Doesn’t really matter, right? What matters is, it’s two stops under the exposure set at the camera and that’s what I like. And what you can start to do is, keep track of these things, so when you need to set up gels in the future that’s how you’ll do it, you’ll know, “okay two stops under, I get that exposure the way I want”. So let’s set up our key light, and what I’m gonna do is, first I’m going to do it wrong, right? It’s always good to do things wrong to start with. And I’m gonna use this light over here, which is basically, there’s a Profoto B1 X here, and I’m just gonna stick this giant silk in front of it. Now this is a beautiful way to modify the light, you guys have seen me use this a bunch of times before. This can be really really pretty, and create some really nice shots. However this light is not controlled, right? So I can tell you right now, that some of it is gonna creep past, and that light that creeps past is going to end up putting some, you know, again white light as it would be, onto the background, right? and that white light is going to make, our exposure. Okay that’s a smidge dark. Come up a bit. I’m gonna add a little bit of light to that. A little bit more. One more down. Cool, okay good, let’s see what that looks like. So again, now I’m two stops under exposure on the background, and my key light is actually set on exposure so you can work towards the main light. Just like, yep. Take half step back this way. Good, perfecto, here we go, nice. Beautiful, right? She has a nice light on her. That’s really nice, right? Except look at the background, right. The background is really washed out. Now if you wanted that washed out look on the background that kind of baby blue then you got what you wanted, right? But that’s not what we wanted, we wanted that saturated background. The reason why, we’re having a problem, is because the light from the front is hitting that background, we don’t want that, right? So we’re gonna use a light that’s more controllable. So I’m going to turn off that light and I’m gonna turn on the light that’s in my octa here, right? This is going to give us a more controlled spread of light, right? I’ll even turn the monitor light on so you can see. We can see that light’s not going to penetrate behind. Let’s get this guy set up. Perfect. Now the reason why I’m not using TTL here, even though you could theoretically do that, is because, I kind, of want to show you guys how things balance out. So I’m using the meter so everything’s consistent. So now again I’m on exposure here, background is two stops under, with a much more controlled light source. There we go and now we got, if we look at these three shots, right, this background is basically consistently
blue in these two, right? Because now light’s hitting the background, here it’s washed out because our key light is hitting the background which we don’t want. So simple as that now we have what we want. Let’s shoot a couple like that. Now it’s important, clearly, with this light, that she works more or less towards the light, otherwise we’re gonna lose her in shadow, right. So that is important. You can see that when you’re working with a light source like that, that’s something we have to do. But look at how pretty that light is on her face, right. Now you can add, let’s say, because I have this light here, and why not use a light that you have, right? Any lights that you have should always be used, that’s part of the photographer’s law. I take this light here and maybe I’ll add a separation light with it, right, because I can do that as long as none of this light hits that background, I can put as many lights up as I want. So I’m gonna throw this in a strip bank, but conveniently was just sitting right there who knew? You know I’m gonna feather it off like we always do with these and let’s see. Okay so that I’m gonna set up that’s my B light. Turn it on and I’m gonna meter it, again just that we metered everything else because now it’s in a box it’s further away, but I still want to make sure that it’s the exposure that I wanted today. Okay that’s showing 5/6, I’m going to drop it a stop. So now again on exposure for my key light, on exposure from my hair light, two stops under for my background light. Alright let’s try that and that’s not terrible right? And you could add more if you wanted to, right? I could add one from the other side if I had one I could do a lot of things. So let’s try a few looks like this, let’s see what that looks like, fun shots. Now with her more forward like this we have to be weary, like in the shadows, but as long as she keeps her chin up, we should be ok. What it comes down to here is that saturation is really controlled by exposure, right? The darker the exposure the more saturated. So let’s, since we got those and they look great Let’s just do a few where we go down even more. Let’s go four stops under. Okay let’s try that. So now we’re gonna get real dark back there. You know now we’ve got this almost like a, Oh that’s kind of nice actually, it’s kind of like a navy. You know towards the light is fine, not quite that far but, as long as you’re working mostly towards the light, good focusing, good, good, here we go. The thing with this light is that, remember, It’s in a grid so if you’ve got somebody who has this great hair like she has, she might throw shadow on her face, but it’s also a soft light so it works you know we got a lot of options. Yeah just a few straight at me, like look straight at me. That’s where, that’s the only time you might run into a situation where, I’m sort of out of focus, where you might have a little bit too much shadow, on one side of the face, but even that I mean big soft light it’s totally fine and if you really really wanted to you could… Bet you’re like “Daniel you just told me I can’t do that” Well this is now not a light source it’s just the bounce, so it will not throw light on the background it shouldn’t anyways yeah, and now we filled in a bit and the background stayed the same, right? Super subtle that could be anything you’ve got, looks really nice. Just one or two more with the bounce. No it’s too much for this composition yeah, because we only have a small frame here, so we can’t go too crazy. Yes that’s it, exactly, right. Okay guys so you see that’s pretty simple right, it’s just a matter of getting the exposure of the gel, where you want it which is oftentimes underexposed, based on your exposure set on the camera. It really depends on the gel of course, and also your background. This happens to be a white background, if it was a gray background who knows? That’s why I say ratio is key, right? You need to know the ratio so, and you’re not gonna know the ratio till you test it and it’s simple enough to set it up. Start with on exposure and then dial your exposure down on that light until you get it where you want it, bring in your key light, your key light needs to not hit the background, or any other lights that you add. They just need to not hit the background, that’s so important for this, it’s really the main tip here. And then you’re good to go, fire away shoot, do all kinds of fun stuff you can change the colour of the background to any color you want, any way you want, any saturation, by using the same technique. So I will put Farrah’s information in the description, so you guys can follow her. Be sure to follow me @DanielNortonPhotographer subscribe to Adorama TV and ring the bell I’ll see you next time, OnSet.