The Difference Between Flow & Opacity
So who can tell me the difference between flow and opacity? Cool. So, flow and opacity work like this. 100% flow, 100% opacity. Let's deselect it Nothing's on crazy blending modes. There you go, all right. 100% flow, 100% opacity. We're getting a 100% of everything. If I go, and instead of 1% opacity, I will go 4%, so nice and low. This I draw once, we don't really see much of a difference. I draw again, I draw again, I draw again, I draw again. So now we're starting to see, see all this unevenness going on here, right? But the only way that we get more color, is if we click and drag again. So, for anybody who has any painting experience, this is kind of like painting with acrylic paint. You paint a layer of color you let it dry, you paint another layer of color, you let it dry. There's no blending, all right even if you're using a very low opacity. In this case here, we can see all the unevenness that's coming from using a low opacity. All right, so if we zoom this out. Let's say we g...
o 100% opacity and even just 4% flow. I am gonna paint, and this is gonna act like an airbrush. And our blending is very smooth and very soft. And our history is showing a lot less strokes. So that means that if you wanna go back, your computer isn't filling up your scratch disk as quickly because you're using less strokes over and over again. So, flow and opacity, I tend to leave my opacity at 100%. I don't really ever touch it. And then I just, I only adjust my flow. So, when I am working, in this case here, with this image. Open. So we're zoomed in nice and close. Brush. I am gonna make this nice and small. Depending on the type of surface I am working on, we'll just slowly... X to make that a little bit higher, so we can see what's up. Do you ever mix up right and left a lot? I am one of those people so there's a 50% chance of getting it right I will probably get the other one. (laughing) So now the case, I am just lightly bringing this along and I am using the smaller brush, and because I am using a lower flow if I happen to go over the edge a tiny little bit, it's not gonna be the end of the world. I can always just go Control + Z, Control + Z, whichever. (laughing) I get teased a lot for the Z and Z thing. We can just slide this in here a little bit. I would just go around the entire dress getting rid of that little tiny halo there. And I would go around her face and her hair and all that because when you do a quick selection, even when you're using channels, you're probably gonna have a little bit of this. So it's just spending the time, and whenever I feel like, oh, my God, I spent to much time on an image, I hang out with some of my painter friends, (chuckles) and I'm like never mind. (laughing) In the time that they do one painting, I have done six composites so I'm like eh. It's not so bad. So if you're ever feeling sorry for yourself because you spend too much time compositing, hang with a photorealistic painter or a sculptor. Or a musician, God, musicians they spend a month on a song only to have somebody tell them it sucks. So, really in the world of art, composite artists, we got it kind of good. So, yeah, that's generally the gist of this crap. Over, and over, and over. So you know we zoom out and we're like, yeah, we're at her waist. We're a quarter of the way there. (laughing) 1/4 of the way finished. All right, so we zoom in, and, you know, I might like draw in and fill in some of the hair. Or I might not, whatever. It doesn't really matter to me. So, that's kinda where I'm looking at this, and like: Okay, this is looking not too bad. Right? Like I said once again, I would probably go in and clean this up. If you're familiar with frequency separation, I'll probably cover this a little bit more in detail, but sometimes if I find that I have a haloing that I didn't notice earlier and I'm towards the end of my composite, I will do a technique that is very common in beauty retouching. Pardon me. The technique is very common in beauty retouching, which is frequency separation, where I separate the color from the texture of the image. So I can manipulate them separately. And so, if I find I have a little bit of halo going on, I will do frequency separation. I'll leave the texture alone, and I will pull the color in on that halo, and then if I have to manipulate the texture a little bit to blend it a little bit, I will. So, if you're not sure what frequency separation is, watch PROtique's video, (laughing) which has been really great for live course or you can go onto Fstoppers.com and they have an article called, The Ultimate Guide to Frequency Separation. And they're both really awesome. They're both great ways to learn. PROtique, of course, is an incredible instructor. You can apply that to composite images if you're trying to make mistakes that you didn't notice before and you want to be able to correct it without having to delete a bunch of layers and go back. So, that's another way that I'll, sometimes, get rid of those halos, if I'm not noticed. Especially if I am doing late night retouching. Sometimes I miss things. (laughing)