History Brush Tool
Below that we have the History Brush Tool. If you ever mess up on an image and you don't end up using Layers for something like for instance if we have this image and I ended up coming into the image and making some sort of a change maybe in this case I end up applying a Filter. I click OK. And, I wish I would've done that on it's own layer because I want the background to look like that. That's known as the Oil Paint Filter. But I wish it wouldn't apply to his face, his arms, and similar areas. Well, I can go to the History Brush Tool which is what I'm in right now and if I paint it should paint with what the image originally looked like when you first opened it. And therefore I can bring these areas back so if I don't want the Filter or any other change that I've made to the image to apply to these areas I can easily bring them back. You can also lower the opacity of this tool, and therefore not bring it all the way back to the original but blend the original version with this versio...
n. And I'm just gonna get his other arm here. You should be aware, though, that on occasion the History Brush will not work. And that is if the original version of your picture is a different size than this one. That means you scaled it, or you've cropped it in a way where the width and height of the image is different that the original. Because then it doesn't know where to align the original image with this newly sized image. Also, if you've changed the Mode of your picture. Maybe if that picture started out in Grayscale Mode, you converted to RGB Mode. It won't be able to use the History Brush then either. And the History Brush, you should be aware, is related to the History Panel. So let's go to the Window Menu and choose History. This is the History Panel, it simply lists everything you've done since you opened your image. There is a limit on the number of steps it will remember, and that limit can be found in your preferences, if you choose performance. In here is a choice called "History States." It should be called "Undos," because that determines how many Undos you get. And that means if you do more than 50 things to this image it will start forgetting the very first step. It's not that it won't apply it to your picture, it's just that you won't be able to undo all the way back to the original. So if this is a list of everything I've done to this image, then what I can do is, if you look on the left column, there's an icon right here that looks just like the tool that I'm currently using. That's the History Brush icon. Well, I can click on any one of these previous steps in that little left column to tell it exactly what I should paint with. So maybe I put it right there to say, "I wanna paint with what it looked like "right after applying the Oil Paint Filter." Well therefore I can come in here and I can apply that look back to the image. It just happens to be that that defaults to the very top portion, and that is always what your image originally looked like when you first opened it. But what that means is you can experiment and get back to what your image looked like at any past state by just going into the History Panel and clicking in that left-most column to tell it what should be the source that you're painting with, with that History. The History Brush. Now, I personally don't use the History Brush all that often, and that's because I instead decide to work non-destructibly by putting most of the changes I'm going to make on separate Layers. By putting them on separate Layers, if I wanted to Undo something I could either throw away that particular Layer, or I could add a Layer Mask to it and paint there to temporarily hide things, and I find it to be much more versatile. But on occasion, I'm doing something quickly I end up working directly on the layer that contains the original picture and I mess up in some way, and need to get back, and that's when I'm very happy that the History Brush is available. Also, you can fill an area from History. So if I select an area like this just rectangular area, I can go to the Edit Menu. There's a choice called "Fill." And one of the choices in this menu is called "History." And that means "do the exact same thing "as what the History Brush did." And when you click OK that brings it back to either what the original image looked like or whatever you have the History Brush set to in the History Panel. The time I do that the most, let me revert this image to get the whole thing back, is when I apply a Filter and afterwards I wish I remembered to duplicate a layer and apply it separately. Let me show you what I mean. I come in here and I choose, I dunno, Find Edges. And I get this interesting look. But I wish I would have duplicated the original layer first so that then maybe I could Mask this, or I could change what's called the "Blending Mode" on it. In the end I wish I had the original picture in that. Well, instead of starting over what I will often do is I'll create a brand new empty Layer, by clicking on the New Layer icon in my Layers Panel. And then I'll just tell Photoshop to fill that Layer. And I'll tell it to fill it with History. Meaning, fill is with what the image looked like when I first opened it. And then maybe I want that to be underneath so I'll unlock that bottom Layer and drag it under. So now I can easily get to that point where it looks as if I duplicated the Layer because I just made a brand new empty Layer and I filled from History. So now I can maybe use a Blending Mode. Just making up use for it here. And now I have that Filter applied in a different way.