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4.2 What Is Image Resolution?

Hi, everyone. In this section, we're gonna talk about image resolution. What is it? You might have heard of it about it before, you might have been confused about it before, basically it's the quality of the image. Okay, will it print nice or will it display nice as a PDF? That's what we're gonna discuss. So image resolution, basically, it's high quality images versus low quality images. Does it look good, does it not? And it comes down to a number, anywhere between 72 and 300. Where do you find that number? So first thing we need to do is go to Window, make sure you're not in preview mode, okay? So hit the W key, go to Window, and go to this one called Links. Your Links panel will show you your images that are used in this document. You can see there, it shows me I've got Image2 used somewhere in this document. Actually, it tells me it's on page 1, so that's handy. What's even more handy is it'll tell me its resolution. So I'm gonna click on it once. And down here in this tiny little window, okay, which is a little hard to use, it'll show me lots of information about this particular image. See this little tab at the bottom here? I'm gonna click and drag it down so I can see more. You can see here, it tells me it's an image, it's a JPEG, it's RGB, all lots of useful stuff. What I'm looking for is this one called Effective PPI. PPI is short for pixels per inch. If you're old school, dots per inch, DPI. It's exactly the same thing, they just call it PPI now. And it's called pixels per inch cuz because if I zoom in, I'm zooming, zooming, zooming, zooming. If I zoom in on the image enough, you'll start to see, it's a little hard to see probably in the video, but you can see the tiny little pixels that make up this image. Us as humans, if we zoom out far enough, we don't see those little pixels. It looks like a lovely continuous image, okay? And basically, say you got an inch squared here, the PPI is, how many pixels are in that inch? So PPI is pixels per inch. So any inch on this page, there is currently 278 pixels jammed into that inch. And basically, the higher this number, the better quality it will look, or appear as a print, or on a screen. If this said 2000, if I zoomed in, you'd see a lot more pixels crammed into that one inch, confused? Yes, okay, so basically, we've got two numbers. 72 PPI is fine, and will look really good if you're going out for a digital means. So like a PDF that's going to be emailed or downloaded from a website or viewed on a website. [LAUGH] Okay, so 72 is as low as you can go. If I use 72, though, and say I get this guy, zoom this up, I'm gonna make it bigger holding my two keys down, Cmd + Shift. If I keep making it bigger, can you see? I'm stretching this image and that same inch hasn't changed size, but there's just less little pixels that get to go into it cuz I'm making it bigger. Okay, and if I get this up to about 72, roughly, I'll make it bigger this way. I don't want you to do, this is a bit of a pain. But you can see I'm getting close to 72, come on down. Let's just say it's 72. I've stretched it so big that if this is going out for digital, okay, that would look fine. Okay, 72 dots per inch on a screen generally looks fine. If I sent this to a commercial printer, though, soon as it gets printed, it will look terrible. That's why 72 is the lowest you can go, but only if you're going out for digital. If you need to go to print, this needs to be as close to 300 as possible. Okay, so at the moment, I'm gonna undo that. Undo, undo, undo, undo, undo, undo, using, remember, Cmd+Z, or Ctrl+Z on a PC. Now, if I was going to be absolutely perfect and proper, I would scale this down a bit more. So I'm compressing it. So I'm jamming more little pixels into that inch. You can see I'm nearly close to that, that's the exact number, okay? Well, for an exact number, that's not exact at all. I'm close, okay? [LAUGH] So it's nearly 300. That's the benchmark. If you want it to look great when it's printed from a commercial printer, you should be aiming for 300. But it is just an aiming, it doesn't have to be perfect. Some people would disagree with me, they say it has to be 300. Okay, but I am less fussy about it because the difference between an extra one PPI and not PPI, nobody on the planet's gonna know. This is my opinion though, remember. [LAUGH] So when you're bringing in an image and you're stretching it out, it's good to just, and you don't wanna go to your boss and say, yep, do you like this image? Great, it's gonna be good. It's gonna cover the whole front cover there. Okay, there it goes. We use this on the cover. And you sell it to him, great. And you print it, and because it's down at 180, it's not gonna print very good. 300 would be beautiful. How do you get it to 300? You can't, okay? Basically it's down to the original photograph. So let's say this is Phil's image, okay? It'll depend on how much he's cropped it and the megapixel of his camera. So its original capture is kinda how it's born, and you can't change that. You can fudge it a little bit in Photoshop, but it's out of the scope of this course. Now, if you wanted to use this as a cover, and it's down 180, you be like, can I print it? I would, okay? Now, this is definitely coming from Dan, whose done a lot of print, but is not a purist when it comes to like pre-press quality guru. And I know enough designers who would be like, it's 180, it'll be fine, and print it and be happy enough with it that I'm confident enough to share it with you. So my minimum is 180. And my highest, there's no point, well, anything above 300 doesn't matter, okay? So 300's the maximum that looks good in print. And how low can you go? I say 180. But you might send it to your printer and they go, hey, that's not good enough quality. Then you might do a test print, okay? Just have a little look, but I'm happy at 180. Let's just look at one more image just to hopefully kind of add a bit more sense to it. So I'm gonna have nothing selected, Import Image. And you can do this with me. From your Exercise file, there's one in there called low-resolution-example. Okay, so I'm gonna bring it in. I'm actually just gonna click once. Okay, cuz I know it's quite a small image. I made it small just as an example. So I'm gonna open up my Links. I close that in between, there we go. So I've got two images. This one here, if I drag it down, is at near enough 300 that I, this one here? Yeah, this one here. Near enough 300, I'm like, yeah, fine, go to print, okay? This one here though, if this is going out to be printed, I need a thousand of these printed for my conference, okay? And I need this to look great, it's not gonna look great at this size. 72 dots per inch will look fine if this is gonna be say, down here, and it's going to be in a PDF that I'm gonna email to people, or downloadable from a website. 72, remember, is perfect for screen, but in terms of print, it's way off. Remember I said kind of, 180, is fine for print, okay? It needed to be, watch this. If I wanna get ready for print, if I scale it down, 88's too small still. That's too small, there you go. Okay, so at 300, it is tiny. It's about a third. So whenever you bring in an image and it's 72 per inch, and you're like, I wonder if it's gonna be big enough? Make it about a third the size, roughly. And that'll be high quality, near enough 300, it's gonna print perfect. Then there's the little bit too casual resolution Dan way, where it can look fine at about 180-ish, okay? So I'd be happy printing that. It depends what it is. If you're trying to sell a Rolex or a Bentley and it's the front cover, don't fudge the images. Get it as high quality as you can, but this is a supporting background image. It's got a bit of noise in the graphic anyway, I'm happy to do it at 180. So screen use is gonna be up to 72. And if it's going for commercial print, it should be at 300, but you can go as low as 180. Don't tell anybody I told you that. The last thing to discuss is let's bring, I'm gonna get rid of the kea, or is it a kakapo? I'm not sure, it's one of the, it's a native bird of New Zealand. It's probably a kakapo. I'm not sure, anyway, the last thing I wanna show you is, so we've dealt with images, JPEG in particular. Let's say I bring in a logo that's been made by somebody. If you're looking to make logos, check out the Envato Tuts+ Illustrator course that I've done. Okay, but, let's go to File. No, I keep going back, that's my old way of doing things. I'm getting used to the new way. If this thing here is in your way, click on the little link. You can kinda pop it back in and out, okay? Nothing selected, Import File. I'd like you to bring in the Logo1-White. Click Open, make it a size. I'm gonna click and drag it about that size. And what you'll notice is that if I go to my Links panel now, and I click on Logo1-White, there is no effective PPI. You're like, where is it? It doesn't have it, it's because is what's called a vector file. A vector file is made by something like Adobe Illustrator, and it means it's resolution-independent. It can be scaled to the size of a mountain, and it will still be crisp and clear. It's kinda more math that involves making it. That's why it's got a really specific look, really hard edges, simple colors. So you don't need to worry about the resolution of images like this. Again, if they come through and these guys are set to Typical Display, they can look really bad. Let's have a little look. You see, if it looks like that, just go to View, and go to Display Performance, and just make sure it's high-quality. I'm gonna scale mine down. How do I scale it, what's the shortcut? Do you remember, it's two keys, they're a bit weird. It's Cmd+Shift on a Mac, Ctrl+Shift on a PC. And I'm just gonna kinda put mine up here, roughly in the corner. That looks good. So now, the W key, sort of big. [LAUGH] There we go, that'll do. All right, that is image resolution. If you're like, man, that blew my brain, you might have to watch it a couple of times. Image resolution is a funny one. I hope this section made it a little bit clearer, but we're done with the images now. Let's move on to the next section where will deal with some long text. I'll see you there.

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