Understanding Curves

 

Adobe® Photoshop® Mastery: Color & Tone

 

Lesson Info

Understanding Curves

Curse isn't the easiest thing to understand if you try to learn it on your own, but I'll help you through it and I'll make it much easier understand you should be aware though, that we haven't gotten deep into adjustment layers yet and it's only when you combine the two together that you truly get the power of curves because right now the adjustments were going to apply will affect the entire picture and that's going to limit us because sometimes we try to pull a contrast let's say in an image and we only needed one spot we don't need it across the whole image, so just be aware that the next session after this one we'll get into adjustment layers and that's where we'll be able to isolate smaller areas within our picture. So if my images here don't look absolutely perfect when they're done know that I would usually have an additional step that I do, which is adjusting things using adjustment layers using some special features there, but we first need to get the overall understanding of ...

curves down so that when we're talking about adjustment layers we can be useful with those adjustments. So curves um a lot of photo shops adjustments behind the scenes are really using curves to perform their adjustments, but what they're trying to do is present you with a simpler interface for instance, we've used the brightness and contrast adjustment well, behind the scenes it's really using curves to do the work it's just not showing you the curve that's being a clyde it's, not allowing you to adjust it with the precision in the control you would have if you were actually using curves. But heck, it's, only two sliders so it's easy to understand you can't go into it and learn it on your own when we use levels levels is really using curves behind the scenes to apply its adjustment is she is presenting us with a simpler interface to do it with it's on ly if you get all the way in the curves where you get all the power of curves and so it's the thing that I would ultimately try to become comfortable with, and once you do, you won't need brightness and contrast anymore. You won't need most of levels anymore, you can just do it all the curves, and you'll have so much more control over what you're doing. Having said that, I'm not trying to talk you into using curves for everything. Use curves when curves khun do something that the other tools that you might be more comfortable with can't do something, then pop over the curves and maybe slowly get more and more comfortable with curves so that you might slowly replace those with curves. But in general, use what you're comfortable with. You want to be comfortable a base to do that and just pop over the curves when you run into something that whatever tool you're used to using can't do it for me personally, you'll find that I primarily used two main adjustments and flutter shop one is curves and the other is called human saturation, and I find that those two adjustments khun do the vast majority of what I need to just about any image and then the other adjustments they're useful and I used him on occasion, but I would say eighty percent of the time I'm using those two adjustments, so today they want to get into curves. When I talk about curves today, though, we're gonna limit our talk about curs, too tonal adjustments, which means we're not going to be adjusting color will adjust color with curves tomorrow so let's, take a look first off to do curves I'm going to usually go to the bottom of my layers panel I'm gonna click on the adjustment layer pop up and I'm just going to choose curves in here's what you get in in curves, there are some things that actress like levels, for instance, we have the eye droppers. They work the same as in levels so if I had a black and white picture I could grab the black eye dropper click on something and it would force it in anything darker than it too black if I used the white eye dropper clicked on something it would force that shade anything brighter than it white. If I had a grayscale picture that isthe with color pictures these do things slightly differently uh we'll get into those tomorrow with curves we have a history graham it's in here right now what's in this particular layer is text so the history ram doesn't necessary look normal because text only has a few shades in it so the history am only has a few lines but it is a history and just like in levels then do you remember in levels we had two sliders where we could force areas toe white orchid four serious to black and there was a hidden feature built into it where it could show us what's becoming black or what's becoming white. We have those same two sliders right here at the bottom of curves they do exactly the same as the upper right and left sliders in levels and if you hold on the option key alton windows you get the same preview that shows you exactly what's turning black exactly was turning white so some of those things are consistent also, just like when we're in levels and a lot of other commands, we have a preset pop up many where if you have curves that you like to apply to images, you could save them into this menu and you would do that by going to the upper right, same place he went in the other adjustments and say, save curves preset and as long as you save it in the default location that brings you to, then it should show up in this menu when you say that so a lot of the things they're consistent between the adjustments but the thing that's difficult figure out is how to think about curves because this curve you can click on and out of dot you khun dragging around and you can have multiple dots and do a bunch of weird things like, how the heck do you figure this thing out like this thing? You know, it might look complicated, and it might be really easy to screw up your image with it. Trust me, it is but it's actually not as complex as you might think so let's see if we could figure out how to think about curves so I have a little slide show is going to help me out describing curves and that's we have going here, so the concept behind curves is absolutely identical to this thing. If you need if you know how to use one of these you already know how to use curves so in case you've never used it maybe have the knob style in your house this controls how much light is in a room if you move it to the bottom the lights are turned off right complete completely black if it's this room if you push us all the way to the top it becomes as bright as you can possibly get in photoshopped the rightest you can possibly get would be white right? Whereas filtering lights off would be black does that make sense but it's not like one dimmer switch that would be like brightness and contrast where you have one brightness control that's extremely limited in how useful it is instead it's actually like having a bank of dimmer switch is just like when you might go up in your kitchen in your house you probably don't have just one light switch instead you could actually label him but you know you're probably already familiar with the ones in your house but imagine you're in a dorm room and you just moved in you might want to label it well so you might have one dimmer switch that controls the hallway leading to your kitchen one for the light above your sink one for who knows what but you could label him underneath in photo shop is actually gonna label are dimmer switches and it's going to label him underneath, but instead of controlling different parts of your kitchen, we're going to control different brightness levels within your picture. So the dimmer switch in the far left will control areas that used to be black, the dimmer switch in the far right will control areas that used to be white, and then you got the shades in between us. Well, you can control, but it doesn't make sense to me to start the dimmer switches in their current position, because if this controls what happens to black, what should happen if I move it down? What's darker than black? I don't know how to darken black any further than it is already. So shouldn't the dimmer switch for black actually start at the bottom? So you start off with no light whatsoever and the dimmer switch for white? It doesn't make sense to me that it starts in the middle, because white is bright as you can possibly get. If that's what you get when used as much light as he possibly can, shouldn't that dimmer switch start up there and then the ones in the middle? Shouldn't they be not the same amount of light like they are right now, but somewhere in the middle, so were progressively using mohr and maura and maur light as we get into brighter and brighter shades now that makes sense to me I don't know if it does to you if it does look at those dimmer switches visually connect them together in your mind with a straight line wouldn't that be a diagonal line that would connect him together? We'll do you see anything resembling a diagonal line in here it is exactly the same well I shouldn't say exactly we only had five dimmer switches in here you have two hundred fifty six imagine you have two hundred fifty six dimmer switches sitting side by side well they're so small in order to fit two hundred fifty six in this little dialog box that it just looks like a diagonal line and it would be impractical to have two hundred fifty six dimmer switches and have to adjust every single one separately imagine how long it would take to adjust your picture two hundred fifty six clicks to kids all the shades adjusted so what happens is you end up clicking on this line in dragging in all of the dimmer switch is near where your mouse is moved together because it would just otherwise be impractical but that's okay it's actually gonna help us that way so here's our curve so we can click on this in drag and create some sort of a shape and that's when it starts becoming a little bit more difficult to understand but it doesn't have to just look at those and think of them compared to where you started now compared to where you started means just think of what the original line looked like the original line looked like that so just remember that shape when you're looking at this I mean, heck, you could just throw a pencil on top to represent the original so if that's the case if he moved it above the pencil that's why he moved the dimmer up what happens when you move any dimmer up you add light brightens does not when you move a dimmer down from where it used to be, he is less light it darkens correct that's, exactly what's happening here and there's no need to hold a pencil up to your screen, though that's kind of low tech for a high tech computer, so if you go and click on the symbol in the upper right that's, how you get to the side menu uh on the curves adjustment layer and if you choose curves display options, you'll get this little thing showing up and in there is a choice called baseline in all baseline does is it puts a diagonal line in there look at the curve itself right now well known second didn't mean zoom in like that okay, look at the curve itself without the bass line with the baseline all of this is the diagonal line in that diagonal lines simply represents where you started that's where the dimmer switches were before you messed with them now that's on by default it's just if you ever get on somebody's machine and you don't see that dying a line you could go to that side menu she's display options and turn on or if you know somebody else in your office that loves curves you could mess with them turned off on not that I'd suggest that so now let's look at how this curve relates to the original line and sieving figure out what the heck it would do look at the area that goes below the original line that's where using less light than you started with the diagonal lines where you started their dimmer switches move him down you're using less light so this fryer's using less light if you move it down a tiny amount you know what happens with the dimmer switch if you move it a tiny amount you barely make a change so here we've barely changed the image well just like with levels you always look straight down to the bottom and you look at this little horizontal bar remember and levels we had one of those with black and left white on the right well it's in here too it's just skinnier and so you always look straight down to that because that tells you what you're working on so here we move it down a tiny amount and go straight down. It means the shades right here, we'd get the tiniest bit darker because they're dimmers have been moved down right here. It's been moved down a tiny amount as well. Go straight down from that. Whatever used to be this bright in the image also got the tiniest bit darker here, though we have a huge change, and if you go straight down from it, things that used to be this bright are going to get dramatically darker, just like in your kitchen. Move the dimmer switch way down, big change, then look at the area where we got above same thing if you move it up in a little bit, you make a little change moving up a big amount, make a big change, and you always look straight down to see what it is you've changed or what you're working on. I know that doesn't help you visualize what would this do to a picture, but hopefully it just gives you a sense for how to think about the curve a little bit. Once we get on a picture, you won't have to think about this as much. So let's go to the side menu, though in here there's another choice called history graham, remember, in levels we have instagram well, you can choose if you want it in here or not just by going to the side menu and going to the display options, which is what brings up this dialogue and there you can say, hey, you want to see history graham that hiss a gram works just like the one in levels, so if the bar chart doesn't go all the way across, then you don't have all the brightness ranges you could have in your image ok, so then let's talk a little bit more actually it's back up for a second in curves do you see the bar on the left? That vertical bar in the left let's figure out what it does it's actually overly simple what it does it would be the same thing as having a dimmer switch in case you had maybe a russian roommate moved in in in russia all they have is knobs instead of up and downs when he's having trouble I'm not trying to pick on the russians I just when I was in russia they had more knobs than up and down so you could do that to help him out. Well, all that would do is preview what would you get if you move the dimmer to a particular height and that's all it does and curves it says hey, move the curve up this high, you end up with that so in this case, it says, if your curve is at this point it anyplace you're making some area of your picture exactly that bright, and if you were to move it higher, you would be heading into these brightness levels so in curves, that's all it does. So if I want to see by moving the curve up this high, how bright and by making something I just glanced to the left and it tells me, hey, if you move it up this eye that's, how bright you get, and if I want to know what it is in the image that I was changing, you look straight down to say things that used to be this bright are now going to become that if you really care about that a lot, you're more than welcome to click on the side. I didn't go to that option's choice there's a choice in there called intersection line, and if you turn on intersection line, what happens is in your curve. If you're clicking and actively moving a dot, your mouse is currently held down your moving around, you're going to find two extra lines in the curve when you isolate just the two lines, it added, usually can't turn off the grid I retouched them out to show you, but do you see those two extra lines that it's adding all that's doing this when you're moving a point is it allows you to follow the line straight to the bottom to say this is what I'm changing something that used to be this bright in my picture and followed to the left this is what it's becoming that's what that does I don't find that to generally be overly useful and I find that it looks kind of cluttered with the grid and there the diagonal line and all that kind of junk so I usually have it turned off but if you really wanted it you find it helpful feel free to turn it on it was called intersection line and it just says, hey, what shade of my working on what's it becoming you still don't know how to think about curves right now you're just getting a basic thing but when you have no clue about is how do you think about it when you're working on a picture we'll get to that ok picture now there are two different ways we can access curves we could go to the top of my screen, choose image adjustments and go to curves and that's fine, you'll get a larger version of the dialogue box instead of going to the side menu to choose curves, display options and that's what it was called to get that little box that you could turn features on and off instead you'd have this symbol the bottom of curves that you could click to show our hide those options so I can say get rid of that intersection line if you're not using the history ram you could say get rid of the history graham, that kind of stuff and you close that up you have the same features in here than you have when you use an adjustment layer it's just the layout is different. I think we used an adjustment layer these eyedropper tools were over here vertically they're just trying to make this more compact. When you use an adjustment layer, I got to this by going to image adjustments curves the problem with doing it this way is this will affect only one layer in my document and it's generally permanent when I'm done, if I save, enclose my image, open it a month later. There's no way to see what I've done it's not gonna have the curve in there it's just gonna have the result of that curve, and so I would prefer to use adjustment layers. It just happens to be the way I have this particular document set up it's going to be more convenient for me to use this on ly because if you look at my document, look at my layers, let me scroll through look at all those layers that's because I'm using photoshopped us a slideshow program right now for those of you that have never used photo shop is a slide show program you could put all of your images in a single document I just have one image per layer and there's a trick we'll share it with you right now just so you know what I'm doing and that is if you make it so that the on ly layer that's visible is the layer that's active none of the other layers are active none of the other layers are visible then I khun just cycle through the layers by holy noun the option key that's all tim windows and using the square bracket keys on my keyboard they're usually in the upper right right near the returner enter key you look like kind of half squares well if I hold down the option key all tum windows and I typed those either one of those brackets I'm either going to make the layer above with layer below visible inactive and that's what I'm doing to make a slide show that just makes it convenient in photo shop so I could do things but because of that my layers panel looks overly complicated look at all those layers it's hard to figure out what's going on in there and that's the on ly reason I probably won't go down here and get to curves through the adjustment layer panel but on every image I ever adjust in general I'm doing it through an adjustment layer you'll learn more about why when we talk about adjustment layers, which is what we'll do after this session so to get to curves I might go up here just for this particular talk because it will be simpler than going to my layers pal because it looks too complicated also there's a keyboard shark cut for this version of curves its command m see it right there because command sees already used for copy used copy some people use copy more often than curves not me but so I might occasionally type that keyboard shortcut to get it to show up the on ly reason I'll do that is just to keep my screen free of clutter so you could just look at a picture and look at curves so on this image I'm going to go to curves command him and let's see what we could do. I like this shape that I found this we're in a temple by the way in southeast asia at the moment and I liked what I found here as faras the shape goes in this little kind of cave almost it's in but what I don't like is the detail that I can see through there that's in the distance and so somehow I want to get rid of that detail I have a couple different options for how to do it one is I could do it just like I do in levels in levels, there was a slider in the upper right that forced areas toe white in here, there's a slider on the right that forces areas to white, and I could just bring this over and see if I could get a lot of that detail to just blow out to solid white. If I wanted to see which areas were becoming solid white, I could hold down the option key alton windows, and click on this slaughter, and I could see exactly where things were becoming solid. White decide I don't want the inside here is sure turn solid white. I want just what's out there now, when I do that, what it's really doing is they added these two sliders for folks that are usedto levels they didn't used to be in curves. If you go into curves and flutter shop like six or seven uh, those wouldn't be there because you'd actually have to know how to use curves to get the same end result. Just look at what it's doing to the curve. All right, look at her curve notice that part of the curves all the way to the top, isn't it? Well, all the way to the top with the dimmer switch means is much light as you could possible use, which means it's turning white, right? And if you look at which part of the curve is all the way to the top it's this whole section here and just like when you use levels to see what curves is doing to your picture, you always look straight down to look at that bar with shades in it. So what it's time telling me right now is all the shades from white to right there are maxed out their dimmer switches, that means they become solid white, so that's going to give you the same end result is being in levels, those air just sliders at the bottom or convenience, you could have just grabbed the dot that's in the upper right and just pulled it over it's doing the exact same thing and that's, we could have two dio for those of you that are still using like photoshopped version three or something and you're using curves, you won't have that slaughter available, so you just have to pull that over and it means force areas toe white. Other things that could have done instead is I could just look at how bright this area is right here in try to find that same brightness level down here and just guesstimate where I think it iss, and just by looking, I'm guessing it might be somewhere in here. I don't know for certain but if that's what I think it is's about this brightness level I could go straight up until we hit the curve and that would tell me where the dimmer switch is right now for that area I could click on the curve and just pushed up in that's like taking a dimmer swish in making a brighter but the other dimmer switches surrounding it are moving with it so the whole image gets brighter okay, but pretty soon I can get it where I can barely see what's there to get rid of any point on the curve just drag it off the grid just think of it as a chess piece pull it right off the board so just grab that pull it off the board now I don't know about you, but I don't like guessing I don't like guesswork I like precision I'd like to know exactly what I'm doing so there is an icon in here that looks like a hand to see right here and I think of how is using an adjustment layer it might be positioned about here remember how they rearranged the layout but it's still in there? I can click on that and now that means when I move my mouth on top of the picture it should do something in curves related to where my mouse's let's see what it does do you see a circle only thing that circle is doing it's it's looking at the brightness level that's underneath my mouse right now it's finding it down here to say how bright is that area and whatever it finds it it goes straight up and shows you what part of the curve controls it it's saying hey where's the dimmer switch for this area so if I go to an area up here that's almost black do you see how low that is? The dimmer switch for this area it would make sense there's not much light in there is low if I go to a bright area do you see how high it is it's all the way in the corner that means this area has its dimmer switch maxed out and I could just move around but if I move right here to where I want to adjust I can see I guessed wrong do you see where it actually is? Circle so it's good not to guess but all that's doing is looking at where my mouse's looking at how bright is that area and finding that brightness down here once it finds the brightness it goes straight up to say hey where's the dimmer switch for that area right now now if I want to change it I could move my mouse over to curves in click right where that circle ist at a dot then I could push it up with one of brighton pushing down if I want to darken, but they made it easier than that. When you have that little hand symbol turned on, you could just move your mouse on top of this area in right within your picture. Click the mouse button when I click that circle got converted into a dot, and now I haven't let go yet. I can simply drag right on my picture straight up or straight down and it's a ziff I have a dimmer switch in my hand, it's just encourages it shows me the dimmer switch is a little dot, and so if I want this brighter, I could drag straight up straight up, and as we get closer to the top, it gets closer to white. If I ever get that dot to hit the top it's going to become one now there's what I consider to be a bug and photoshopped that I've been trying to talk adobe into changing, and that is if I ever hit white by getting that dot just watch curves don't watch the image, get the dot all the way to the top. If I go further than that, it thinks I want to pull it right off the board, you know, get rid of the dot, which I think is stupid. I should hit the top if I move any further it should just max out would be like you go into your kitchen and having a dimmer switch and if you move it past the top the little handle comes off in your hand it's stupid okay it makes absolutely no sense whatsoever on earth I mean it's literally like grabbing your dimmer switch it comes off in your hand so just be careful if you go all the way the top and it goes away just don't let go yet move down a little bit until you're right at the top I think I might have talked him into actually change in the next version will see if you see that changes because of me I yell that now I could have done the opposite I could have clicked on that area and dragged down to say less light less light less light if I hit all the way to the bottom it's gonna turn black of course if I drag beyond it dimmer switch comes off in my hand but um so the main thing we've learned so far is we can click on the hand we can click on the picture it'll target that particular brightness levels so I can brighten her darken it the only problem is everything else moves along with it so sometimes the russian your picture is a little bit different than what you want ok then let's work on this one I'm going to go into curves, I'm just going to type command them to keep the interface clean, but usually I'd be creating adjustment layer to do this, move this over a little bit and I'll click on the hand and come over here. And when I look at this image main thing is it's pretty darn light, I'd like to darken it up, and so I moved my mouse on top of the image and click on the area that I'd really like to concentrate my darkening on. But click right here and drag down. Now it's not just that area that's changing, because if you look at the shape of the curve and you compare it to the original line, pretty much the whole thing's moving down and that but let's say I want to now get this area right here backto how bright it used to be. What do you do in your kitchen if you accidentally bumper dimmer switch and your dining room goes dark and you liked exactly the way you had it? When you just put the dimmer switch back to where it used to be? You do the exact same thing here, so you just move your mouse on top of the thing that got too dark, click the mouse button and then don't even look at your picture look at curves. All you're going to do is move the newly added dot right back up to where it used to be and it will go back to its original brightness so I'm just gonna click on this building drag straight up until it's right back where it used to be all right so now that area's back to its original brightness so let's see what we've done to the image I'm going to just take the preview checkbox turn off and then turn it back on notice near the top of the image that building out there has barely changed does change a teeny bit the reason for that is do you see this curve is not perfectly lined up with the original right here and also it dips down right after that if I add let's say two dots here to try to really get it to perfectly match then the building one change it all but the top is largely not changing in the bottom where it was darker is changing a lot a question yeah when you say click on an area you were talking about a place in the emir or so you're not what I thought was happening was that you were adjusting certain tones and they stay burton told throughout the image so when I was talking about this I should mention that if this bush like thing down here where originally clicked was the exact same brightness level as the building back here then when I moved my mouse on top of that other building, the little circle that shows up in curves would be sitting right on top of the same dot that was used to adjust this area down here I can adjust to areas separately is long as they're different in brightness in the original so if I turn preview off here and you look at this image and you compare this building up here to this bush down here the bushes darker and that's the on ly reason I could adjust the two areas separately and it's not thinking about the top of the photo versus the bottom of the photo it's thinking about how bright did these two areas used to be and how bright are they becoming now? It's completely totally based on brightness it's not based on position within the image earning like that and if when I move my mouse onto something else like let's say this tree over here I can't adjust this tree separately why looking curves look at where the circle is it sitting right on the dot that I have already moved if I try to adjust this it's the exact same brightness is this and that's the on ly way curves can isolate areas is based on brightness yes but if I understand it correctly it's adjusting it like horizontally like two dark this not not like two dark this way offered vertically it doesn't matter who are well vertically in curves is your brightness it's like a dimmer switch sewn up means bright down means dark and so whenever I make a change I'm always moving the curve up or down um but within your image it is unable to isolate like a building from a car it's just able to isolate the highlights from the shadows you know it isolates things based on brightness, so as long as two things are different in brightness, then I can adjust them separately and curves. If two things are identical in brightness adjusting one will affect the other the same amount because that's all this does is thinks about brightness in this ization we make things that used to be this bright, brighter or darker. But let me just more images before you get a better sense for it. So anyway here's before if I turn preview ofthe here's after before and after so far all we've learned is I can click on a hand I can click my picture and it's like having a dimmer switch for that in everything else, since the same brightness is that then if something else is a different brightness, I want to adjust it a different amount I can again click on it, drag it up or down just like a dimmer switch but it affects everything that's at brightness sometimes it feels like it's isolating the bottom of the photo or the top of the photo no it's completely brightness here you're looking at a gate that's like all the way open so it almost is up against the wall and I just wanted to see about controlling brightness of various areas eso when I go in here click on the hand tool if I don't have the hand tool active when I go out here whatever tool was active in your tool panel like a paintbrush or ah eyedropper or the hand tool whatever will be active excuse me in orderto have it think about what is in curves you need to click on that little hand tool so I'm going to click then here and dragged down to say darken cool I'm going to see if I can make the area on the left brighter it's not gonna be able to isolate things on the left is just based on brightness so if the stuff on the left is brighter or darker than what I've already adjusted then I should be able to get it separately I can tell that by just moving my mouth on top of it and if the circle is in an area of the curve that I haven't adjusted yet then I could adjust it separate if that circles really really close to another dot gonna be limited but if it's far away that I can easily do it so that means I can easily adjust this area to see where my mouse is right here because it's really far away on the curve no problem if I want to adjust this area is getting pretty close in any change you make is going to be actually pretty dramatic um but I could brighten that up talking down and then go to this little bright areas they want to brighten their darkened but you still don't really know how to think about curves yet all you know is looks like a dimmer move it up it brightens down it darkens and it can on ly isolate things based on brightness so let's talk more we got a curve look at its overall shape in compare its overall shape to the original line that's in their original lines the dying no one in look at what part of our curve is steeper more towards vertical compared to the original line so that be one spot words steeper right? So let's think about what steeper might mean imagine you have a picture of a snowman made out of snow so it's white and you have don't have a nose on it you don't have eyes like kohl eyes you just have snow right? So a snowman is goingto have a brightness range from maybe pure white to something about what I'm just going to pick something twenty five percent gray maybe in its brightness range well if you think about where that would be in a curve. Pure whites right here. Twenty five percent. Gray is actually this first line that's right here. So if you go straight up from those two areas, pure white usually has much light, as you can possibly use twenty five percent. Grey usually has it's never switch about here that's where the diagonal line is. So what would happen to the snowman if we took the darkest part of the snowman? That was twenty five percent great. To begin with, we took it's dimmer switch and brought it way down. So the darkest part of the snowman where the shadows are, wouldn't it become a lot darker? In fact, how do I figure out if I move it down this far? How dark's not gonna be? Well, don't can't you glance over the left take preview how dark it's gonna be so that means that the brightest part of snowman was still be white. But now the darkest part of the snow will be that dark. Wouldn't that make it easier to see the shadows during the snowman before the shadows were really similar to the highlights? Wasn't that much difference just a little bit, but afterwards you took the darkest part of the snowman used a lot less light in it, you made it that dark and now those shadows will be prominent it's going to make it so you can much more easily see the texture and the detail of snow doesn't matter if you followed my example right there not all you have to know is in a curve if you make it steeper more towards vertical anywhere it's going to be easier to see detail you have a wood door like here you have a wood table in front of the studio audience and the wood grain is very similar to the base color of the wood there's not that much different than a lot of wood doors you take the base color of the door, you leave it alone, but you take the grain part and you darken it tremendously suddenly there's a bigger difference between the wood grain and the base color of the door and you can easily see the detail there do it with anything you're wearing a black outfit you could barely see the texture well in this case instead of darkening things, you could take the brightest part of your outfit brighten it tremendously it's going to be easy to see the texture here's just a greater brightness range in, they're easier to see, so in this particular curve there are actually two spots where steeper not only there but they're so let's see if we can use that for anything I mean a type command them to get to curves but no, I would usually use an adjustment after I get into curves I'll go to the little hand tool and usually if you want to add contrast that's what making it steeper actually does is it increases contrast whenever you do that detail pops out usually you could use the brightness and contrast control I'll show you why curves is better in a few minutes I'm going to go into here and what I would do whatever I want to pull out detail in anything is that would move my mouth onto that subject matter and I would try to find a bright area within it even if it's a black outfit I'd look for the brightest part of the black and let's just say it's right here and I would click then I would find a dark area in the same object let's say it's right there and I would click there's the part of the curve we want to make steeper in order to make more detail come out make it easier to see detail now I have three choices on what to do if we look at this curve to make it steeper in between the two my three choices are move this dot higher when they make it steeper well his dimmer switch moving it hires gonna brighton I could grab this dot and move it down if it's a dimmer swish that's going dark and things isn't it or I could do both how do I figure out which one to dio? Well, I just look at my picture and I say would look better if this had some more darkness to it or somewhere brightness to it we're both so sometimes you're not sure so you just guessed you say I don't know so I can either grab these dots directly within curves or I could move my mouse back to wherever I originally click to create them so I'll click here in the dark parts and I could drag straight down as I do that it should start to become easier to see the texture that's in that area I could move my mouse up to where the bright area wass or I can just click on the dot manually within curves and I could drag that up to say brighton and in this case the colors are shifting in weird ways there's a reason for that if you looking curves I didn't really get the dot that I had earlier you see there's two dots real close to each other and when I drag up noticed the picture it suddenly looks weird well, I knew that was gonna look we're just by looking at the curve if you look at the curves you see the two dots and there's a flat spot between him we'll talk about what that flat spot means in a little while, but for now you should know that usually I don't add the dot and then blab about it a lot and then go back to my image instead. Let me just start fresh get rid of these dots. I would usually just click on the dark part of my picture of that object, dragged down a phone, a darknet, then click on the bright part of that same object in drag up if I want to brighten and I won't end up with that weird looking flat spot, which should make my image look weird, you'll see what that means in a little while now, let's see if I, if it's easier to see detail in texture in that area, I'll turn preview ofthe here's before here's after is it easier? See the texture that's in there now? Unfortunately, if I didn't want the bottom portion of the photo to change with green stuff is I'm only going to be able to get it back to normal if it is not within this range that we made steeper because we need that part to be steeper to get the effect we want so I can move my mouse out here and say, hey, where is this innit? If you look at it it's the same point as something I'm adjusting do you see the circle shut up? Same spot is the dot what that means is this area is the same brightness as the dark portion that I adjusted so I can't adjust it separately and this is where an adjustment layer will be useful. I could say just don't adjust this part of the bottom by painting we'll get to that uh but I will be limited so the main thing is make it steeper if you want to more easily see the detailer texture and something was tried in another picture here is just some desert um in let me show you why you don't want to use brightness and contrast here is brightness and contrast brightness and contrast has a contrast slider and some people think that that's great it'll prove the contrast of my picture well, it doesn't always contrast usually means if you increase it it's easier to see the details and if I bring it up here, it just doesn't seem to be doing that much and it's not helping it's not bringing out the detail let's find out why we're gonna go to curves what the contrast control does and brightness and contrast is it makes the curve steeper, but it does it in the middle of the curve centered in the middle and as long as your image contains a lot of bright stuff and a lot of really dark stuff it khun be helpful look at this particular image though in look at its history graham the history ram tells you what's in your picture what shades are used in which ones aren't and look at where it's really really tall really really tall means takes up a lot of space well go straight down from the areas that are really, really tall and look at how bright they are aren't they in this general brightness range that's where all this stuff is in my picture if this thing was perfectly centered in the picture if that bar chart was perfectly centered, brightness and contrast works great because it makes the curse steeper right in the middle but most of this image is way over here on the right it's not going to be what we need. So if you ever hear of people telling you to use curves in what they instruct you to do is make an s curve. Some people will say that what they mean is add two dots and make it look like the letter s by doing this if they ever tell you to do that, tell them toe learn that brightness and contrast does exactly that, meaning that they could use something simpler it would give them the same end result in what they're doing is they're using curves in a way that is generic and it's not something that will be helpful for most images what we want to do is target a very specific part of this image and be able to have control over it and to do that we need curves so here's what I'm gonna do I'm going to go to this I'm going to try to get the texture that's in the flat parts of this desert to just come out like crazy so it's easy to see so what am I going to do? I'm gonna click on the bright part within that flat desert and I might drag up the little spit to brighten it or I could just leave it alone by just clicking the letting go then I'm going to click on the dark part within the desert not the cracks in between but the actual flat desert part and I'm going to see if I could get a dot there and I'm gonna strength's straight down if I can but unfortunately these two things air so similar and brightness watch what is happening in curves if I add a dot for the bright part and then I go to the dark part it thinks of him is the same they're so darn close so let's do it manually all I'm going to do is drag across this part of desert in curves I'm looking at a circle do you see the circle look at the part of the curve that it travels across the sea where it is just remember what's the highest in the lowest it goes to it looks to me like it went through about here to about there do you think because what happens is when you move your mouse on top here mention your clique it grabs the dot that's near what you clicked on it if there's already adopt there it's going to kind of grab it if they're too are too close together you might have to do it manually so here I'm just gonna grab this strike straight down if I move left to right it all by accident this is like having a snowman and taken the dark part of the snowman grabbing his dimmer pointed down I could make a ridiculous amount if we need to inspect it to see if there's some you know weird thing and there I could do that but most the time is going to make it a little bit steeper so I'm gonna turn preview ofthe here's before here's after if you make something steeper it will be easier to see the detail that is in it if the area that you need to make steeper is very similar to begin with you know the brightest and darkest parts are so similar you might have difficulty using the hand tool in clicking on those two areas because it's just going to grab adopt that's already on the curve so sometimes we have to manually adam but it's only when they're really really close together now I could separately adjust the dark parts that are in between if I move my mouse there and in curves it's far away from the area have already adjusted now it can click there make that even darker or lighten it up only a small portion of the image though it's going to change there but the main thing to take away from that is make the curb steeper and it's easier to see detail you're increasing contrast in a very specific part of your picture now let's do the opposite instead of making it steeper if you look at this curve noticed that this part and that part are becoming flatter and that's where it's going to be harder to see detail if you want to go back to our dimmer switch analogy what if your kitchen your dining room are dramatically different in brightness the dimmer switch for your kitchen's hi the dimmer switch for your dining rooms low and you then moved the two dimmer switches to the same height well if he had similar lighting in the two rooms when they become the same brightness well in here moving them to the same height means let's use the same model light in two areas where it used to be different and so let's see if we can do that here is a sculpture that I shot when I was in russia in moscow and in it I can see the detail now on my screen here I can barely see the detail on the monitor I can see it easily I'm not sure what the feed is as far as how much you can see it but there's detail in there I want to make this a silhouette so it's just a solid black shape so I'm going to go to curves and I could do this in a couple of ways one is sense it's really close to being black already and all they want is black I could move the lower left slider over until I can't see the detail anymore and I can tell you without even looking at the picture it's gonna be to move it right there you know how I can tell? Look at the bar chart the bar chart tells you what you have in your picture and it's saying we have a lot of this dark stuff and also someone there in the image we have some of this other stuff and you see how there's a distinct separation between the two when that's the case you can often gas that there's a really dark object that's the tall stuff nearthe left and there's brighter stuff so I could just pull it to here but let's say I didn't want it to truly be black well, what I could do instead he's just come in here with the hand tool and click on the darkest part of this wherever I think that might be or just drag across it just ran across it in looking curves at where the circle goes you see the with that the circle goes and I could add a dot on both ends of whatever the highest and lowest is that it goes to but in general it's going to be the width of this little part of the history and I could move those two dots to the exact same height if it's the exact same height it's going to be consistent in brightness across that area I have three ways that I could do that I could move this dot down to the same height is that that's going to fix that dimmer switch darken I could grab the lower dot moving up to the same height as the other one if it's a dimmer switch that's goingto bright or I could meet halfway by bringing one down on the other up that's going to both bright and dark and so I look at my picture and say what I like to brighten their dark innit in this case and the good like the darkened so grab the upper not just going to click on it and curves not even gonna look at the picture you can use the arrow keys to move it if you want it once that goes perfectly flat between them then it's like having all the dimmer switches for that area at the exact same height using the exact same brightness therefore across that area so in my image there isn't gonna be any detail because it's the same amount of light across that whole area but now do you see that my sky got to dark? Well, go on, move to where your skies too dark, click on it and if he accidentally bumped a dimmer switch in your kitchen you like the way it used to be when you just put it back to where it used to be. Well, I like the way my sky used to be, so I click on my sky I look in my curve I'm not even looking at my picture and I drag it straight up until it's where it used to be now this guy should be back to its original brightness it'll be off a little bit in some areas because you see how it's going a little bit above here I could always add another dot and kind of help it now it's going to be exactly the same brightness down to here then I'll start going dark so you see it's only the edges of the sky where it's a little darker that are being affected let's try another one in this case I do not want to change the wall but I want to change the door I can do that is long asked the wall and the door different brightness because that's the only way curves can isolate areas is they have to be different in brightness. So what I'm going to do is move my mouth onto the picture in click on the thing I don't want to change just gonna click and let go with the little hand tool turn on and I'm never going to move that dot by never moving the dot clicking on that wall just locked in the brightness, so if I don't move it not going to change, sometimes you preempt here you're having to fix things by just clicking on something, they don't change, then I'm going to come over here to the door. I'm not gonna actually try to pull out some detail if you look closely at the door there's actually an x on it in some other markings, I think it's what they sometimes do when hurricanes gone through and like the authorities have come through and checked this house, they do something and they make marks to say how many people live there, and if they found them all or something that might be it, but anyway, I want to pull out the detail there, so I'm gonna click and drag, I'm not clicking, I'm just dragging and I'm looking at where a circle is going do you see the circle jumping around? I'm dragging over the area where I want the detail to come out and I'm just looking at highest and lowest of where that circle goes that looks like approximately here to about there was about it I look at the door and say well to make the detail come out, I think I'm going to need to brighten the door by dark and it's gonna be hard to see, so that means that moved the upper dot straight up, you see it becoming a little bit easier to see the detail in door now, the wall I'm going to try to get not to change right now. I think part of it is changing the reason for it is I clicked on the wall, but if you look at the area really close to where I clicked it's a little bit below over here a little bit above over here so that we one exact brightness that I clipped on didn't change but things the little list bit brighter did change the things the little list bit darker did change, so if I turn preview ofthe I'm guessing the wall is going to look like it changed its not a lot of so what I might need to do to prevent the wall from changing it just at another dot in there to kind of help the curve stick to that line I might need to add another one at the bottom let's see start to change a little less. I could add another dot has pulled us down here so now it's being consistent all the way to here see if that's enough getting pretty close, but you see how I'm semi isolating the door it's completely based on brightness and get the detail to pop out. This is gonna be so much more useful when we know how to use adjustment layers, but there's still a little bit nor incurred so far we've learned it's like a dimmer switch. She moved up to brighton down to darken. You could make it steeper to exaggerate things or flatter to make things more similar make it perfectly flat you cannot see the detail, but then there's one other thing and that is this. If you look at the original line that's in here, that's the diagonal if you go from left to right and you follow that original line, you're always going uphill. If you go from left to the right and follow the line uphill, then look at the curve that's being applied and do the same thing go from left to right if you're not going uphill the whole time, then you're gonna have a special effect in your picture, do you see that part where is going downhill? Let's try to figure out what the heck would that do well to figure out what the heck would that do let's go back to the simple concept so here if you start on the left and you go to the right it looks almost like stairs you're going upstairs are josie walk that direction what would happen to my picture if we took this dimmer switch on the left side the one that controls black the one that would usually to use no light whatsoever and we did that what would happen to black wouldn't we suddenly use as much light as you possibly could and they become white then look at the one on the right side that's where white is it would usually use as much light as you possibly could but what happens if we do that too it suddenly areas that used to be white we're gonna have no light and whatsoever were black that's weird we're getting the opposite of what we usually have whenever you get the opposite of what you usually have one word for that is invert you're gonna have a negative of your original what used to be dark is going to become bright we used to be bright is going to suddenly become dark you know not to completely understand it all you have to do is know that if you go to curves and I make the entire curve go downhill from left to right watch what happens first I'm going to take white, which usually has the dimmer switch all the way to the top and I'm going to turn the lights off by grabbing that dimmer point to the bottom lights are off now across the whole picture then I'm going to take what used to be black and I'm gonna turn the lights on by bringing this dimmer all the way to the top so if I turn off preview whatever used to be black is now white you know we have the opposite and brightness of what we had previously it's a negative now it would be rare to do that to the entire picture like this because we have a command under the adjustment menu called invert and it does exactly that it's using curves to make it go the opposite direction what's going to happen instead is you're going to add a few dots to a curve you're goingto accidentally make part of it go downhill, it'll be completely by accident and whatever you do it you're gonna be o I think I screwed up the whole image and you're goingto start off by going I don't know what I did I don't know if I'm good with curves, but you're just gonna look at the curve and say is any of it going downhill if you go from left to right that's the part messing up your image so tried to eliminate that maybe don't move the stock quite as far and then the image will look more normal now we can use that we can do it where we make special effects and stuff watch I'm going to try to keep the sky looking relatively normal but I want this stone arch that were looking up at tau look weird so I'm gonna click on the hand tool and I'm gonna click on this dark part of the stone and I'm gonna click on this bright part of stone let me see if that's the same brightness is the sky I think it's a little bit darker, okay? And I'm going to make it go downhill between the two so I could grab this dot and move in above this one wouldn't that make it go downhill between the two now moving it up though that's goingto what if it's a dimmer brightened the image dramatically s o move this straight up until it starts going downhill look at that weird stuff that's because it's going downhill oh there's a party over here that looks semi normal we'll move your mouse on it look in the curve isn't that part going uphill? If I need this part to look weird? Well, maybe I'll grab the dot in the corner just go all the way like that now this part's looking somewhat normal turn it would have to make it go downhill, you know? But I'm not going to get that weird we'll leave it like this, but the main thing is the sky is looking weird and I wish it didn't so I moved my mouse out of the sky and I say, where is the sky? Oh it's right in here do you see in the curve that part's going downhill and I don't want it to fine at a dot toe limit where it is and try to get that part to go normal? I'm not able to completely isolate the sky because the sky isn't it completely different in brightness? There is some commonality between the two, but I can try the main thing is don't accidentally make your curve go downhill if your picture ever looks weird there's one of two reasons for it happening you've done one of two things you've either made the curve go perfectly flat, perfectly flat means no detail whatsoever and if you did that by accident suddenly look at your picture and you say, hey, there used to be detail on that thing, whatever it is there isn't or you've allowed the curve to go downhill somewhere and if you go downhill, you get weirdness not only weird brightness, weird color, so previously I don't if you remember me working on a picture, I think it was this image I think and I got it to go do something weird with colors started messing up everything and it was because the curve went flat and then downhill okay sometimes making it look weird is a good thing here is in three d text that's not really three d but it's supposed to have someone of that look if I gotta curves and I wanted to look more interesting I could just make the curve go up and down so that is not going up the whole time I could click and make this look like it has a couple dot senate point up and down and up again and what we get from three d text we get more of metallic text interesting it's just because we're forcing highlights into its certain areas enforcing shadows into others if you want to get really weird there's something that's not useful in a day to day basis but it's in here so somebody is going to ask about it and that is there's a pencil to see the pencil there's actually two modes to work in you can work in this mode on the left which is where you click toe add little dots and you pull on them or you can use a pencil where you just draw your own kerf me dd dd and so if you want really weird stuff use a pencil make an m or a w and you're going to have it going up and down so many times you're going to get weirdness you will not be able to draw a circle because what would a circle mean a circle would give you to brightness levels he'd have to dimmers for one brightness level doesn't make sense but if you want weird stuff and you just like funkadelic's you know stuff try grabbing the pencil draw your own shape when you're done drawing your own shape there is a button in here called smooth, which means just smooth out the shed the shape watched smooth I'll hit again smooth and again smooth keep it in it and you're going to get close slowly back towards that okay but if you ever draw your own shape oftentimes it's hard to draw a really smooth one, which means it's hard to get smooth transitions in your picture so clicking that at least once we usually smooth out the end result and if you ever get the curves and the little hand tools great out and issues not workin the way expect the last time you used curves used the pencil and it just remembered that so you need to click back on the little icon next to it and that will get you back to where you have the little dots and you could do your own thing all right so curves looks like this if you look at the diagonal line that's in it it's actually, just like having a bank of these, which means it's actually similar to use one of these, it just gives you a heck of a lot more control than one. And right now, your head's about to explode with information about curves, but we're going to end up doing is after we take some questions, we'll take a break and we'll be able to use curves now for the next day and a half over and over and over and over again so that by the time we're done with that day and a half and you see how to do it where it doesn't affect the entire picture, it's going to become so much more useful, and I think you'll like it, it's just you need a bit of an intro first, so I hope that helped you guys to understand curbs, and so if you have any questions, we had any questions in the audience first, otherwise we'll go out to the interwebs. I'm really curious when you're taking those points, you're going mostly up and down what happens when you're moving left to right? Okay, we'll just think about dimmer switches. If you had a banker, dimmer switches and you reach for one. But by the time you're done your hands over there, it means you're working on a different part of your picture than what you originally thought you did so whatever you see me working with curves, I'm always moving straight up and down if I ever move side to side it's by accident because it would literally be like walking up to a bank of dimmer switches in grabbing for the one that would control the light above your sing but you end up with your hand of the one that controls the hallway it's a matter of if you wanted to adjust that you should've started there to begin with move straight up and down some people move him sideways, but I don't I would have started wherever that dot ended up with horizontally started moving it there when you're moving a layer around if you want to move perfectly up and down, you can hold shift and the object what can you do the same thing when adjusting a curve and hold the shift key? Well that point well, a couple things first off if you're using that little hand icon and you're clicking on your picture to do it, you can't move it side to side regardless of how you drag it's always going straight up or straight down so that's going to keep that limitation in when you are clicking manually on one of the dots and moving I don't know of something that constrains it. I don't think shift well, but what I do if I want to move it straight up or down. Yes, I use the arrow keys on my keyboard. It will move it up, down, left to right. And if you hold shift there, think of it as turbo, meaning that it is going to move it further than usual, and so shift up shift down just move means moving a lot up a lot down. Then I let go of shift once they get to the general area, want. And now, it's. More like fine tuning when I go up and down.

Class Description


Part of the Complete Photoshop Mastery Bundle. Become an adjustment master by learning how Adobe® Photoshop® thinks about color and tonality. You'll go way beyond the basics and learn how to use the most powerful, precise and versatile adjustments. You'll also see how all of the Adobe® Photoshop® adjustment options relate to one another so that you'll be able to easily pick the best tool for the job at hand. • Scanning Line Art (pure black and white graphics like your signature) • Optimizing Grayscale Images • Professional Color Correction Techniques • Matching the color between multiple images • Getting the most out of adjustment layers • Color Manipulation Techniques • Sharpening Strategies


Software Used: Adobe Photoshop CS6

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