All right, so let's take a look now at the king of all adjustments in photo shop and that would be curves I played around curves a little bit just demonstrating some of the basic concepts that are involved well, not even demonstrating you know concepts of curves but just demonstrating what happens when you destroy an image essentially but let's take a closer look at curves let's start off with the beginner's guide to curves the training wheels guide to curves because really at its core curves is essentially the levels adjustment with a few extra bonus features, so let's just use curves as though it were levels because by now we all have mastered levels or at least understand the basic concepts having seen the same basic adjustments in a couple of different places. So down below my history graham display, you'll see it the far right I have a little white slider and at the far left I have a black slider so that's our levels adjustment essentially that's our black and white point for the ...
image and lo and behold, we have that same ability to hold the vault key on windows or the option cheon macintosh while dragging the in this case white point slider to get a clipping preview of our white point adjustment or same thing with the black point we've already seen this it's like review suddenly curves is simple ok, it gets more complicated, but still we're off to a pretty easy start, right? What about that mid tone slider in levels? That's a basic overall lightning and darkening of the image with the focus with an emphasis on the mid tones? Well, I just go right to the curb, so the curve, which is not a curve at all when we first start it's just a straight line going from bottom left the top right, but it's just kind of like this physical control, it feels like where we can reach out and grab it and maneuver it manipulated as needed if I go to the middle of that curve line and just click and drag upward to brighten or downward to darken. Well, that's easy, obviously I'm swinging that anchor point in this case a little bit wild normally be a more modest adjustment, but I'm not big on subtlety, so something like that might be a little more typical. All right, well, that's pretty straightforward, we've got our white point adjustment of black point adjustment in our mid tone adjustment were already familiar with those concepts when it comes to working with levels, for example, and even to some extent in adobe camera raw let's take things a little bit of a step further, I'm going to reset oh, this is a good time to talk about resetting an adjustment layer, because curves is one of those where you might get yourself into a little bit of a mess, depending on how heavy handed you get with things. And so you find yourself making a mess of your image with curves down here at the bottom, we have a reset control, that little backward curved arrow, kind of like an undo button, and that will reset the current adjustment in this case curves to its original starting value. So in this case, a straight curve going from bottom left to top, right? Well, let's dabble with this curve just a little bit more. I'm going to grab the bottom left anchor point that's my black point and I'm going to drag it inward and then I'm going to take the white point up here at the top and I'm going to drag it inward and what happens to the image? Well, besides the fact that we have obliterated all sorts of detail in the photo, what we've essentially done is increased contrast so the curve, when the curve gets steeper, then we have mohr contrast in the image that's pretty straightforward when the curve gets more shallow like this when we have less contrast in the image. Pretty simple so now we just have to envision what we want the curve toe look like to create perfect contrast in the photo and what it really boils down to then is thinking based on tonal values in the photo so the most common the most famous the most wonderful curve of all is the s curve, which is so named because if you take off your glasses and squint very carefully and twist your head it looks like the letter s kind of sort of I mean we could make it look a little bit more extreme that's kind of like this script s sort of but what's happening with this curve by the way you're learning how to read a curve which is tremendously valuable and you didn't even know you were learning anything, did you? It didn't feel like learning did it so we have this esseker what's happening what we already know what's happening if we think about what we've just talked about a steeper curve increases contrast a less steep or um or shallow curve reduces contrast. So what are we actually accomplishing? We'll forget about the curve for a moment if you look at the image, you would say we have increased contrast significantly, actually, but wait a minute parts of the curve are less steep than they originally were well, what we've done is we've increased contrast we've steepened the curve for the mid tones and we've made it more shallow for the dark shadows and the highlights what that really translates into is increasing contrast and then tapering off because once again I'll reset how do we accomplish this sort of contrast with levels for example, we have to bring in the black point and bring in the white point and we lose all sorts of details in the process with curves we can be a little bit more sophisticated because we can create that s curve where we've increased contrast for the mid tones obviously in this case I'm still exaggerating the adjustment but I've increased contrast for the mid tones and now it just tapers off to the highlights in the shadows. In other words, I'm not clipping mohr highlight detail or more shadow detail I'm just adding contrast where I really wanted so we've got that contrast notion we've got that basic brightness notion what it really relates to I think of the curves adjustment as a before and after adjustment down on the bottom grady and we have those before values so here's black here's middle gray, here's white obviously those are luminant value so you can sort of pretend like the image was a black and white image and think about what that would relate to and then the after version is over on the left, so if I dragged my curve upward, why is it that dragging the curve upward causes the image to get brighter well, let's take a look at the actual curve notice that by default I have this little line that tells me where the curve used to be and now I can see where the curve actually is and so middle grade for example on that bottom grady and that's my before value so any pixels in the image that had a brightness value that equated to middle gray now let's follow that line straight up until we hit that anchor point hit the curve and then I move over toward the left and boy that's much brighter than the value we started with and just obviously by logic we can see that since the entire curve except for the black and white points, the entire curve is above the original starting value, which is to say that every single total value in the image has been brightened except for the whites because you can't get any brighter and accept the black because we want to leave that alone who that's exhausting. But now we have all the tools we need to be able to adjust that curve to achieve the result that we're after in the image let's take a look just a couple of random examples we'll just create some arbitrary examples here. For example, I might like to add a little bit of drama to that sky it's pretty bright and blown out maybe I will want to darken the sky and leave the rest of the image alone at least that's going to be our example for the moment? Well, let's see where do the brights live in the image? Well, they live in the sky obviously we're talking about the image itself. What about on the curve? Well, it's the brighter stuff so let's go ahead and start at the bright end of the curve the right side of the curve and I'll just click wherever I think on the curve might be appropriate all click on the curve that adds an anchor point aiken drag downward and sure enough, I am darkening the sky agreed, however, I'm also darkening the whole entire rest of the image because the rest of the curve came along for the ride and this is where I think burbs can get the most challenging when you're especially when you're just getting started is that now we have to use thes anchor points to kind of manipulate to bend the shape of that curve. But it forms these busy a curves where each little adjustment you make affects the curve way over here and so it could be a little challenging, but the idea here is that in this case I want to darken down the highlights, which I've done, but I don't want to darken down everything else and so I will add another anchor point in order to kind of normalize the curve and so maybe you know something like this and then I'll find to this one and just go back and forth between those anchor points trying to get this sort of lower portion of the curve as it were to be as normal as possible sometimes it might take a couple of anchor points to accomplish that and then using this section of the curve to adjust that sky and again when I'm demonstrating these adjustments it's much better at least for your purposes not so much for the image to make that adjustment really exaggerated so that you can see more clearly what's happening in the real world when you're applying adjustments to your images subtlety is usually best and it really doesn't take much in curves to have a significant impact on the photo in fact, what I generally tell photographers who are new to curves using a mouse to adjust an anchor point don't move the mouse just think about the mouse move in and that will cause you to subconsciously move your hand just the tiniest little bit so that you don't even realize you're moving it but it moved in that's going to be enough of an adjustment for the image it's all you need another great trick it might be a little bit difficult to see these little anchor points a pretty small but the anchor points down below here are just outlines their empty in the center and the anchor point up here is filled in the one that's filled in is my current anchor point they got that way because I clicked on it and dragged I'm gonna drag it down a little bit too far here once I have an active anchor point, I can use the arrow keys on the keyboard to move that anchor point so up and down effects brightness so we're brightening by moving up darkening by moving down left and right just determines where we're focusing our adjustment. Oh, I need to impact the brighter areas, so let me move it over to the right or I need to impact the darker areas, so let me move it over toward the left it doesn't you don't have to on ly move the curve straight up and down with those anchor points you can kind of show me back and forth left and right watching the image, looking for the actual effect that you're you're intending for the photo. All right, we're going to reset that once again and get back to that s curve so maybe something like this at a little bit of drama to the darks come back over here and then maybe brighten things up a little bit then realized was a little too strong so I go back and mitigate the effect but something like that allowing us to increase contrast without worrying about clipping the highlight and the shadow details which is a real problem to a lesser extent now it is the brightness contrast adjustment was updated a number of versions of photo shop ago so that it's not quite so harmful it has a little bit more self control you could say with levels it's very difficult to get maybe the degree of contrast you want without losing highlight or shadow detail with curves that is very very easy well at least in concept sometimes it could be a challenge don't get me wrong it could be a little bit of a challenge to find it exactly the right adjustment exactly the right position for those anchor points and especially if then I start to get a little more sophisticated I want to kind of dark in this down a little bit mohr oh but I want more contrast in the sky so I'm gonna move this part of it upward in this part down we're remembering the darks the brightest highlights down and then I'm gonna try and get the what is going on with my thiss was starting out so good and then oh my goodness what happened actually I did that on purpose to show you an opalescent sky so you know just to give you a sense that it's easy to get out of control especially making kind of big adjustments with curves if you start adding too many anc her points to that curve. It can start to feel a little bit difficult to clean things up.