Understanding Images | Kray Mitchell | Skillshare
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15 Lessons (50m)
    • 1. Introduction

    • 2. Introduction to Formats

    • 3. Raster Graphics vs Vector Graphics

    • 4. Raster Graphics

    • 5. Vector Graphics

    • 6. Web Formats

    • 7. Print Formats

    • 8. RAW Files

    • 9. Color Modes: RGB vs CMYK vs Pantone

    • 10. DPI vs PPI

    • 11. Resizing and Resampling

    • 12. Megapixels

    • 13. Retina Graphics

    • 14. Google Images: Due Diligence

    • 15. Outro

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About This Class

Understanding Images is an introductory course into the world of Images. It's not a graphic design course, but you will walk away with a basic understanding of graphics and how they work.

We will talk about some of the formats for web and print, discuss some of the file types and applications you will come across and we'll learn the difference between color modes!

You won't need any applications or files for this course.

So what are you waiting for? Let's get learning!

Meet Your Teacher

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Kray Mitchell

Sometimes a teacher, always a student.


He's a devil's advocate, he's a strategic thinker, he's a technologist and he's an educator. Since 1997 Kray has been building websites and diving headfirst into the world of web and technology. From building websites to implementing technical solutions for companies of all sizes, he has designed for print, directed for TV, taught in the classroom and mentored the eager.

Kray loves to teach, speak and inspire. With an eclectic background in Information Technology, TV and Film, Graphic Design, he brings a wide range of experience and expertise to all his projects.

See full profile

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1. Introduction: welcome to understanding images. This is an introduction course to the basics of images and image principles will be talking about things like PP I vs DP I Raster versus Vector Graphics. RGB versus C M y Que and we'll be talking about formats as well. This is not a graphic design course, though. If you're looking at getting into graphic design, this will definitely give you a good introduction to images. In general, this course is not in depth, nor does it cover any topic in depth. It's only meant to get you to understand images better. I hope you enjoy it, and I hope you learn a lot. 2. Introduction to Formats: Now we're gonna talk about some file formats. We're going to discuss both working fouls, also known as application files for both Raster and Vector based graphics. And we're also going to talk about some of the output files for both Web and for print, so let's get right into it. 3. Raster Graphics vs Vector Graphics: we're going to take a look at the difference between a raster and a vector based image. So I've got an example here, down at the bottom. I've got my name written twice once in Raster format, once in vector format. Now, from this distance and at this size, you really can't tell the difference. But if we wanted to skill up this image, we'd see a major difference. So let's start with the left hand side in the raster image. Have we zoomed in on this little area here? We would see that this text is actually made up of a series of squares, also known as pixels. Now, if we look at the vector side of things when you zoom in on that same area, you can see that it's still very crisp and sharp. It doesn't matter what size you scale a vector graphic, too. It's always going to remain nice and crisp. It's not until you convert that vector graphic into a raster, also known as a bit map image, and turned it into pixels that it no longer becomes scalable. When it comes to resolution vectors, air also resolution independent, they don't have a PP I associated with them until they're converted. Whereas the raster images, as we've already learned, have some kind of peopie I resolution associated with it, whether it's 72 pp. I for the Web 300 peopie I for print or 600 or whatever PP I that image happens to be going back to this Rastra graphic again. We can see it this size again. It looks very crisp and clean, but that's the size it was exported at and the size it was meant to be displayed at as we learned in the PP I video. If we tried to skill this up to fill into a larger space, the image goes all fuzzy. If I zoom in on this image, you can also see that like the type example that I just gave. It's made up of a series of squares so you can see that it's a bunch of different blocks of color. That win zoomed out eventually make up an image and of course, the further I zoom out on this, the better quality it's going to be. This was a 72 PP. I image at 200 by 300 starting at 300 by 200 I scaled it up, so it looks really good when it's at the size it's supposed to be. It doesn't look good when we try and scale it up. Another quick example. I'm just gonna take the paint, brush here and draw quick line with it now. From here, it doesn't look too bad, but again, if I start zooming in on to it, you're going to see that it's made up of a bunch of pixels and has a very kind of fuzzy were soft edge to it, the further you zoom out the Chris Burger that's going to get. So when it comes to Raster graphics, you're always going to be dealing with pixels, and you're gonna have to deal with things like those fuzzy edges. You could zoom in really close and manipulated image on a pixel by pixel basis, which gives you a lot of flexibility when doing photo manipulation in a photo shop or other raster graphics programs. Now let's take a look at vector graphics, so this truck here is actually made up of a bunch of mathematical calculations that make up a bunch of lines that turn into a bunch of shapes, colors and eventually a piece of art. Well, it looks like this truck is one piece that's actually made up of a whole series of different pieces. As I move my mouse over the image, you can see the different pieces that make up this image, and I can actually go ahead and select those pieces and move them around if I wanted to, so you can see that it really is made up of hundreds of different little pieces that would put together in the right places. Make a graphic. You'll also notice that if I zoom in extremely close onto this, um, 6400% on this, it's still very crispy and claim so again, vector graphics can be scaled indefinitely from very small to very large, with no loss in quality. It's not until you convert that vector into a raster graphic that you start to have the issues with the pixels per inch. In my previous example, I also showed you what it was like to draw a line in the Raster program. I'm going to the same thing in the vector program here, and you can see now that I've drawn it out. It's very crisp and clean. If I go ahead and zoom in, it remains crisp and clean. It doesn't get those soft edges. You'll also notice that when I hover my mouse over it, it just gets this little blue line because that's all this is. It's a line with what is known as a stroke, and the stroke is essentially the outline to that line, and I can control how thick or thin it gets by simply increasing the stroke or reducing the stroke. You'll also notice that there's a series of dots that go along this line. These dots are called points, and they actually make up the line itself. I can select these different points and manipulate how that line looks. You'll also notice that the DOT has a couple of extra lines sticking out of it. Those handles allow me to change the arc of the line, so you really do have a lot of control over what you build now. Of course, if you wanted to build something that was photo realistic, it would take an immense amount of work and skill to create an image like that. That's not saying it can't be done because it absolutely can. But if you do want to get into photo realism, you're gonna have to work very hard at making that happen. With raster graphics, it's usually some kind of photograph that's going to be the base of that image with vector graphics Pretty much every logo created for Fortune 500 companies or any company really is going to be created with the vector so you can see this sheet here these air Fortune 500 logos. This is from unified media l l c dot com But you can see here that all these logos are very simple. A lot of them are single or only two colors, sometimes only three colors, but they're created with vectors, so the look good small and could be skilled really large without any loss in quality. So just remember, when you're dealing with raster graphics, you're gonna be dealing with pixels, and it could be problematic if you scale down an image and then needed at a larger size. When you're working with vectors there scalable from really small to really large, and they're built on mathematical equations again, masters mostly for photographs, vectors mostly for logos and Leinart. But it's not specific to those, and you will see both of those intermingle in your careers. So that's the difference between a raster graphic and a vector graphic. 4. Raster Graphics: So when it comes to graphic design, the £400 gorilla in the room is Adobe Photo Shop, by far one of the longest standing graphic design programs and one of the most widely used photo shop is the leader in photo manipulation and has been for quite some time now when we're talking about Photoshopped documents, The native extension for photo shop is dot P S. D. So photo shop document. That's the standard foul. Now, while this is the native foul of photo shop, there are a few third party applications such as Pixel Mater, which I'll show you shortly that will also open this format. Now the big downside to photo shop is its cost. Now it'll be his stopped making boxed software. They only have their what they call Creative Cloud editions, which you purchase online, download and then install. And it's actually a monthly cost now. So if you wanted to get Photoshopped by itself, it would cost you 1999 us a month to use this program. Now, if you go ahead and you pay for this on a monthly basis and then stop paying, that doesn't mean that you're no longer be allowed to use the software. It means that you'll no longer be able to update this off where so you could quit now and then. Keep that software for a while and signed back up in a year and get the latest version. Or more recommended, is to stay up to date with your software. Now one of big competitors in the industry is Carell Paint Shop Pro Now, unlike Photoshopped, paint shop Pro is not available for Mac. It's only available for Windows so well, you don't get the cross platform compatibility like you do with the photo shop paint. Trump Pro is still an excellent and wide use program. It's quite a bit cheaper than photo shop. It's only about 60 or 70 bucks, I think, and the native file format for Paint Shop Pro is P. S. P. Um, if you're an older Carell user, you might remember Carell Foretell Paint, which is a similar type of program and had the extension dot c p. T. So if you're a Carell user or if you work with anybody that's a krill user. You might see the PSP or CPT formats again. These air native application formats and these air working fouls. So in last year, sending to somebody else that uses Photoshopped Paint shop pro. You shouldn't be sending these fouls, and you should be saving them out as a different output format, which will discuss a little bit later. Moving on there is gimp Now. Gimp is quite popular because it's free. Gimp stands for new image manipulation program, and it was originally designed for Lennix. Now, aside from its free price tag, the other good thing about campus is available for Windows, Mac and Linux. So similar Photoshopped It gives a wider range of uses rather than just Windows just Max or just Lennox. And the default file format for gimp is X C F, which stands for experimental computing facility format. Now one of the downsides of gimp is that if you're doing raster based graphics, but you need do it for print by default, Gimp does not support Sam Y K. Now I don't use gimp personally, but I have read about a couple of different plug ins that allow you to work in the C m y que color space. But I cannot speak to its effectiveness, having never used those bludgeons before now. I had mentioned earlier when talking about photo shop about pixel mater. Pixel Mater is a Mac only app, but it's really ah, good photo shop competitors. It comes with a lot of the same kind of features that Photoshopped does, but without the price tag. Pixel matter by itself is only $30 to purchase from the Mac App store, and like I mentioned previously, it also opens PSD files. So if you're working with somebody that uses photo shop, you can exchange files back and forth quite easily now. The default foul format for pixel mater is P X M, so it, uh, stands for pixel later, obviously now, hopefully, picks later will release a version for Windows in the future, but currently it's only available for Mac and for the iPad. Now, when you're looking at just Windows, there's a whole bunch of graphic programs out there as well for Windows. Being a Mac user myself, I don't want to specifically mention any of them, as I've never used them with pixel mater, gimp, paint shop and photo shop. I've actually used at one point or another, so I feel a little more comfortable talking about them. So just a quick review. We've got Photoshopped, which uses the Photoshopped document, or PSD. We've got Carell Paint Shop Pro, which uses the PSP file format. We've got gimp that uses the X C F format, and I had also mentioned Pixel Meter, which uses P x m. So all of these are raster based programs there used to build and manipulate graphics. You can have layers. You can have different color modes, bit depths and all sorts of cool features in these programs. So if you're just starting out in graphic design, you're gonna be working with at least one of these programs at some point in your career. 5. Vector Graphics: Now that we've talked about raster graphics programs, let's move on and talk about vector graphics programs. So again, the £800 gorilla in the room is Adobe illustrator like Photoshopped. It's been around for quite a number of years and is a leader in the industry. Illustrators, by far the biggest vector program out there, and its default file format is dot E I, which stands for Adobe Illustrator moving on from Adobe Products. We take another look at Carell and Carell has Carell draw again? This is a Windows only program. It's not available for Mac and similar to Illustrator. It's a vector based program. The default file format for a krill draw file is dot CD are now. Don't get this confused if you're a Mac user with the dot CDR format, which stands for CD Rahm. If you have been a Mac user for a long time and you've ever created a disk image from a CD , you'll note that DOT CD ours is the default foul tape for that. So again, don't get that confused with a Carell draw document, which is also dot cdr. Another big competitors. A is in escape, which is free program similar to Gimp except for vectors. Again, this one is available for Windows, Macs and Lennox, and it's completely free by default. Escape uses XVG foul format as its native format, which stands for Scalable Vector graphic, which we're gonna talk about Ah, a little bit more coming up in the output formats as well, because it's widely used on the Web as well. So, with scalable vector graphics or SPG, you can open those an escape. You can open those in illustrator and CorelDraw as well. So again, these were kind of the three big ones in the industry. There's a bunch more out there, and because I previously mentioned picks later, I wanted to mention it again because in the newer versions they have a plug in that they call Vector Mater, which kind of switches your palates and layouts from its standard image manipulation version of their software into vector based. So it gives you a lot more shapes and a lot more tools to use for creating vectors. Now, this is still kind of a new feature of pixel mater, and it currently does not support opening things like GPS files. So right now, It's not a full on solution for Vector. But given how quickly the pixel mater team works and the features that I've seen added over the years, I see this becoming either a standalone program or a much more in depth plug in for pixel mater that will allow the important export of things like UPS as well. So a quick overview on the graphics programs we've got The Adobe Illustrator, which is the big one with dot AI files. We've got CorelDraw, which is another big one for Windows that uses the CDR format. And we've got Escape, which uses the SPG, or scalable vector graphics as its native format. Again, all three of those programs will allow you to use GPS or encapsulated post script files. And those are the type of files that most printers are going to request when you're sending things off for print, 6. Web Formats: now that we've had a chance to talk about some of the working files. Were those applications specific file formats such as the PSD for photo shop and the ex CF for gimp. I want to go into some of the output or delivery formats, so I want to start with more of the Web based formats so you can see here. I've got a couple of different images on the screen here on the left, I've got a photograph, and on the right, I've got two different vectors. So the first vector is very simplified vector just as a late Grady intimate. Whereas the one next to it of the camera is more of a photo realistic Victor. Now, based on what type of image you have will lead you to what type of output format you should be using. Now, keep in mind. Once you've saved out a image into any of these formats, they should never be edited again. These air final output and you should never use them again. They're being exported for a specific purpose for a specific use using this format. If you need to use it for something else, then you really need to go back to that original file and re exported out for whatever purpose that you want to use. So let's talk about some of these common Web formats. The 1st 1 I want to talk about is the J. Peg, and the J. Peg was created by the Joint Photographic Experts Group, And the J Peg, much like its namesake, is generally used for photographs. So, like the picture of the cat on the left here, anything that's a photograph format when you're trying to put it on the Web, the J peg is going to give you the best compression while maintaining the best image quality. Moving on with the formats. We've got the GIF, or sometimes known as Jif. But let's face it, Jeff was a peanut butter, not a graphics format, and this was created by CompuServe and stands for graphics interchange format. Now the gift isn't used as much as it was back in the early days of the Web, and most of the time, when you see a gift these days, it's an animated GIF. Any time you're online and you see the little animated videos that just keep looping on themselves, most of the time, it's an animated GIF. Now, before I talk about some of the other features of the gift, I also want to mention the ping dot PNG, which stands for portable networks graphics or to some people, it stands for pings, not gifts. So the reason the ping actually came to being was back in the day when the gift was more popular. They were actually gonna start charging to use its compression algorithm so much other developers got together. And like, No, we're not gonna do that. We're gonna create our own similar format. Now, as previously mentioned, J pegs are more meant for photographs with gifts and P and G's. They're more meant for solid colors, logos and Leinart, so more similar to the middle image. But you're going to see used a lot on higher end images as well, such as the vector on the right of the camera. And the main reason for this is both gift and ping support. Transparency's. So if I wanted to put either of these two vectors on a different color background, I could do that quite easily, providing that the original source for that file was transparent. Now what do I mean by that? Well, if I take this image right here of my little character there and I just move it on top of this image, you can see that it's transparent because you can see all the way around that edge. So if I saved this out as a J peg, it would essentially create a box. The same size is the image and make the background white. So if I wanted to put it on a black background or a green background or a yellow background , this image would have a white square around it, so it doesn't look very good. So any time you want to put an image such as this, or is the camera on to a different color background and the image is transparent like this than a gift for a PNG is gonna be your best option because it allows for that transparency . Now, I personally prefer P and G's, and a lot of graphic designers will say the same thing because you end up with a higher quality format with lower file size. Um, GIF has been known to have a lot larger file size for the higher quality and If you actually look at a lot of the animated GIFs out there, you'll notice that they're quite small in the dimension size. And the reason for that is because even at that small size, it's usually still a Meg or two megabytes and size to get that Now, more recently, we've also started seeing another format coming into play, and that's called the S V G. Dot s V G stands for scalable vector graphics. So if you've created an image such as this camera or my little icon here in something like Adobe Illustrator, you can actually save it out directly as a dot S V. G and S V G makes it so just like a standard vector graphics. It's scalable, so when you're using it on the Web, you can display it really small. But you could also display at larger and not losing equality. So with the S V G, the file size itself is going to remain the same, regardless of how big you presented on the screen now with the retina graphics, as we had discussed previously, at 200 by 300 with a vector graphic, it could still be displayed at 203 100 but a look fantastic on the retina screen. If we were using just a photograph such as the picture of the Cat here and we wanted to displayed on a retina screen at 300 by 200 we would need to have that double sized image and shrink it down to 300 by 200 to get the same kind of effect. The downside about the scalable vector graphic is that it's not supported by older browsers , but these air the formats that you're going to run into when you're talking about Web design and you're gonna be creating images to go on the Web. The J Peg, the GIF, the ping and the scalable vector. Graphic these air what you're going to run into most often. And please keep in mind that when you're creating images for the Web that you should be creating them again unless you're doing retina graphics at the size that they're going to be displayed. So even if you're saving down a PNG graphic if it's 8.5 by 11 to start with, don't save out in 8.5 by 11 PNG file Save it down to the size that it needs to be in the end, so those are the most common Web based delivery formats. 7. Print Formats: Now let's talk about some delivery formats that you would use for print again. These are just the most common ones that you're going to run into. And I want to make the statement before we start that. Obviously, print graphics and Web graphics are completely different beasts. So where with the Web formats, we were really concerned about file size and actual dimensions of the image. When we're talking about print, we generally end up with fairly large files. Sometimes 20 megs, sometimes 50 maids, sometimes a terabyte. You can get all different size of files, depending on what you're doing, what you're creating. But when you're going to actually print your document printers, they're gonna want one of a couple of different formats, and I want to go through those with you. The 1st 1 is the tiff. Now I've noted it. Here is T I f F. But a lot of people we use just t i f is well, and it stands for Take the interchange file format, and this is by far one of the more common and longest standing formats in the print industry and similar to the Web. You do want to create this document at the same size that is going to be printed at. So if you're going to be printing in at 11 by 17 then you need to create your document at 11 by 17. And if you remember back from the PEOPIE I video because it's going to print, you want to make sure that this file is also going to be at least 300 peopie I or higher anything below 300 peopie I and you're really going to start losing quality in your print work now we'll Tiff has been popular for quite a number of years. The PDF or portable document format has started taking over as the preferred format for a lot of printers, and it's also worth noting that a PdF file can use both raster graphics or vector graphics and still be edited Herbal later. And the other format that you're going to hear a lot in print is the E. P s or encapsulated post script foul. Now with the E. P s. These air always gonna be vector format files. The PS is kind of a multi application file. If you watch the previous videos on the application formats the PS technically could be used as a working foul, but it usually ends up as something you save on adobe file into to send to somebody else. So, for instance, you're getting a designer to do you A some business cards, um, letterheads of graphics for your vehicle and a billboard ad sending them in E. P s of your local will allow them to use your logo on everything from the business card all the way up to the billboard all in the same file. So you would never send out a picture of a cat in an E P s format, but you would use the PdF or TIFF option for the cat. That being said, if you're simply sending some vector art to get printed, perhaps you created a beautiful poster in Illustrator and you were getting at printed 11 by 17. You could use teff, PDF or E. P. S. When sending to the printer again. There are numerous different formats out there that I did not cover here. I just wanted to make sure you had a basic understanding of the most common formats out there for both Web and for print, not only for your working fouls but for your delivery fouls as well 8. RAW Files: so just a zai did a separate video for megapixels. I wanted to do a separate video for the raw format as well as both of them really have to do more with digital cameras. So what is a raw file? While most people consider a raw file to be like a digital negative, it's an un processed version of your image that contains a bunch of extra data about the lens type and all that information about the picture that you took. So if we open up a raw format image in photo shop, it opens up this raw editor here. Now this particular image is a dot cr two file because it came from a canon camera. If you're using other tapes, a camera such as Nikon, you might see any F Pentax uses PdF, and you're going to see a whole bunch of other ones, depending on the type of camera that you have. If it has the ability to shoot raw now, as soon as you open it, you're going to see that you've got a whole bunch of different selection options here. You can immediately change your weight balance. So as it was shot, let it selected automatically Daylight cloudy, whole bunch of other options. Plus you've got an additional options such as exposure, contrast, highlights and shadows So you can see in this cloudy white balance. It's it's essentially removed all the shadows you can see if I drag this down. It's really adding to the shadow area. So it really does give you a lot of extra control over your images. And we haven't even gone past the basic tab. There are multiple different tabs across the top here. I'm not gonna get into any of these. This is really getting into in depth photo management here, but I just wanted to show you how this differs from a standard image. When you open up a standard image in photo shop, you're not going to see this window and you're not gonna get all these extra options. These options are essentially pre processing before you actually open the image. So if I go ahead and click open image now, the image is gonna open. As I had created it there and told it to be the cloudy set up and on all the other stuff that I just played around with their CNC has got that late, Hugh. So there really is a lot more that you could do with a raw image. And if you are going to be getting into photography, it is recommended to shoot in raw. Even if you're a really good photographer for those instances where things just don't happen right in, the exposure is not quite correct or anything else like that. This just gives you a lot mawr ability to correct for that, and you lends corrections and color attractions and all that that other thing before you even get into editing the image. So there you have it. That's raw images. 9. Color Modes: RGB vs CMYK vs Pantone: Now we're going to talk about the most commonly used color models that you're going to run into. The 1st 1 is going to be RGB, which is used by digital devices, and the other two c m y que and Pantone are used in the printing industry. Let's start by taking a look at our GP. RGB is recreated like I said, using screens by shooting three different color lasers together to create different color spectrums in each pixel. Those colors are red, green and blue. Using these three colors, the screens reproduce all the colors that you're able to see in photographs and anything else that you're displaying on screen. When we move from the world of digital into the world of print, we're going to see a lot of C. M y que with C M Y que printers use these four primary colors cyan, magenta, yellow and black to reproduce the CME like a color spectrum. Now, when you're designing stuff and using a computer, you have to keep in mind these two different color spectrums. Now we're in photo shop right now, I'm gonna show you a little feature that's it called the CME. Like a preview. I want you to keep an eye on the RGB on the left. When I switch into the C m y que color mode, you can see that the green and the blues both get darker. Let's see that again. This is because C. M. Y que and RGB reproduced colors slightly differently. So if you're gonna be using a computer program to create anything for print, you have to make sure that when you're creating it you created in the CME like a color space. They go to create a new document. Here. You can see that there's color mode, and it's currently set the RGB color. There's also see him like a color. You could also create bit map, grayscale and lab color. Most of the time, though, you're going to be using RGB, C M y que and sometimes gray scale, though most people will start in some kind of color mode and then reduce the colors from there to design their gray scale the way they want it. So these were the two primary color systems that you're going to be dealing with. Sometimes, though, you're going to run into Pantone now, the Pantone matching system is a proprietary color system that goes beyond the C M y que spectrum to reproduce brighter and better colors. Now there are certain Pantone colors that can be reproduced with both seem like a and RGB. But there's a lot of colors that cannot be reproduced. Using the CME I can are to be color spectrum, So if you're designing something and you decide to add Pantone colors into those designs, then when you go to get them printed, if you actually want them printed in those colors specifically and not be closest matching C M I K, it's gonna cost you quite a bit more because Pantone ings for quite expensive. The benefit of Pantone ings, though, are that they're each numbered with specific identification numbers for each color, so it doesn't matter where you go to get that color printed. The color is always going to look the same with C M Y que. Sometimes the colors can vary depending on the printer that you're using. So any time you're paying low costs for printing and you're getting it done digitally, especially, you're not gonna be getting Pantone inks. You need to go to ah higher end printer that offers Thebe Pantone matching system and can reproduce that color spectrum. Remember that Pantone or for high end expensive colors, C M Y K r for standard printing and RGB is for the screen. Those are the color types that you're going to run into most often. 10. DPI vs PPI: Let's talk about D. P I. P. P. I and Resolution. Now, when we're talking about resolution, it could refer to a couple of different things. If you're talking about any kind of computer monitor or TV screen and you're referring to resolution, you're usually referring to the dimensions of the screen, the width and the height being used. So you commonly see numbers like 1920 by 10 80 which the screen that you're looking at now is currently set at. You might recognize those numbers because they're the same dimensions for 10 80 high definition. If this were 7 20 high definition, the dimensions would be 12 80 by 7 20 The resolution of this screen will depend on many different things. The format. For instance, in television, if it's gonna be 7 20 or 10 80 or four k and on a computer, it will depend on the manufacturer of the monitor, the output from the computer, the video graphics card and what it's capable of. L putting and you could see all sorts of different numbers. You could see 14 40 by 913 66 by 7 68 12 80 by 10 24. There's a whole bunch of different resolutions out there when you're referring to actual monitors and televisions. When we're talking about D. P I and P P I as resolutions, there's a very important fact that you need Teoh Differentiate the two when somebody says dp I or dots per inch. This is actually a technical term in the printing world. If somebody says DP, I the most likely Mean PP I were pixels bridge. If you're any kind of graphic designer, you should be referring to it as PP I. If you want to get something printed, it needs to be at least 300 pixels per inch. If you're gonna be displaying images on screen, they can be as low as 72 pixels per inch. Now you're gonna hear some people say that that's a myth, that it doesn't matter what the pixels per inch resolution is when displaying on screen. It kind of does, and a kind of dozen. It really depends on the final output. If you're working on a high definition video that absolutely the pixels per inch doesn't matter and you can go with a higher pixel per inch, such as 300 peopIe. I just like you wouldn't print. But if your images air gonna end up on the Web, you really do want to use 72 pixels per inch as your resolution. The reason for this is because it will reduce the overall file size, and those images will load quicker. Went on the Web. Let's take a look. A an example. Hopefully clarify some of that information that I've just given you. We're gonna take a look at this picture here, which was taken directly from a canon camera shot in raw. So this is the highest resolution that this camera can shoot now, when I say raw and I say J peg thes air different formats for images and we'll talk a little bit about formats later. So we're dealing with resolutions. We're going to notice a couple things. So first, this image is very large. It's 51.3 megabytes in size. Now the pixel dimensions, or how it displays on screen. So currently it's displaying at 5184 pixels by 3456 pixels. You'll notice down here that the with the night are being displayed in inches. I could go ahead and change this drop down and select pixels, and you'll see it's the same as above. But I wanted to make a note about this while we're going through. You'll also notice that the resolution is set to 300 pixels per inch. So what we know from this is that this is an image that is suitable for printing. At 11 by 17. When this is printed, it'll come out nice and crisp and clean. Watch what happens when I change the resolution. From 300 to 72 you'll notice that a couple of things changed, but something didn't change the width, and the height in inches didn't change. It remained the same, so this image will still print at 11 by 17 but at a lower resolution. So what does that mean for the image? While you'll notice on the left hand side here that this image got smaller previously, you could only see the nose. Now you can see the whole face. You'll also notice that the image size has dropped down from 51 mags to just under three megs and the dimensions instead of being over 5000 our 1244 by 829. So the size of this picture being displayed on the screen has gotten smaller, but the print size has remained the same. The difference being when you print this image, it's not gonna look as sharp and crisp because of the resolution change. So if you think about this as a pixels per inch kind of thing, a pixel is just a small square of color. So in a one inch square, at 72 pixels per inch, there would be 72 little squares crammed into their at 300 pixels per inch. You would have 300 of those little squares cram into the same spot, so that's where you get the higher quality from. With more pixels crammed into that inch, you get a much better look and feel to it. So if I go ahead and just click, OK, you'll see that this overall size of this shrunk. So we're currently viewing it at 25% of its original size. If I go ahead and view this at 100% so it's standard size, you'll see that it's still fairly crisp and clean. So this is what I mean when some people say that it's a bit of a myth because it's 72 pixels per inch and 300 pixels per inch. This image looks great on the screen. If we went and printed this image, it would come out a little fuzzier and a little softer than the 300 pixels per inch version . But it wouldn't be too bad. Where the problem comes in is when people take small images and try to make them larger and print. Um, and I'm going to give you an example here, so this is the same image at 300 pixels by 200 pixels at 72 pixels per inch. If I go back to the image size panel on this image, we can see that it's only 175 k So it's very small, very nice for trying to load on the Web. But you'll also notice that the prince size has dropped drastically as well. Previously, it was 11 by 17. Now it's currently four by two. The reason for this is because not only did I lower the overall resolution from 300 Teoh, 72 but also changed the overall dimensions. You'll remember the original images over 5000 pixels wide, and I've dropped it down to 300 by 200. So now here's where people run into big problems with printing. They go in, they find this image on the Web and assume that they can use it and print it. It's a cute picture of a cat. They want to blow it up to Lake 11 by 17 again. So let's take a look at what happens when we try and do something like that. So we know that for printing, we should be printing at 300 pixels per inch. If I just go in here and change the resolution from 72 to 300 let's see what happens will notice a few things. One will notice that the dimensions jumped up from 300 by 200 up to 12 50 by 8 33 will also notice that the preview on the left got quite a bit bigger, but it's quite blurry and blocky. If I go and switch this from pixels back two inches, you'll see that that print dimension still the same it's still only four by two, so we're not increasing the actual print size. All we did was trying add resolution to it. So a lot of time when somebody's asked for a 300 pixels per inch image, this is what they end up doing. They check the size of the image, see that it's 72 and simply just up the resolution. If I do that, we end up with this image here. So what had happened originally when we took that very large image and shrunk it down? We removed a bunch of data with that to make it smaller and reduce that file size. Now we want to try and make it larger for print, so we've simply try and change the resolution or the pixels per inch. Unfortunately, when we made it smaller, all that information was lost. So the computer is just making its best guess at what this image should look like. Not quite what it should look like, but it's similar. So this is what happens when you try and take a small image and try and make it larger. You really want to make sure you keep your high resolution images because if you ever need it again for any kind of printing, you want to make sure you can print and have it come out nice and crisp and clean. 11. Resizing and Resampling: this video is meant to go into a little more depth on re sizing and re sampling images I had touched briefly on this in the PP I video, but I wanted to go into more depth and talk about it a little more in detail. So when we look at the image size window of this image, we already know that there's two different dimension sizes. There's thes screen dimensions shown in pixels. Then there's the print dimensions I've got showing in inches. On top of that, we've also got the resolution, which displays the pixels per inch is when you look at this window here, you can see that both the width and the height have this little lock icon in between them. Which means if you change one, the other is going to change. It's gonna be proportionate. So if I change this from 17 by 11 down to, let's say 11 you can see it brings us down to about seven inches. You'll notice that the resolution doesn't change, though this is what is known as re sizing an image. We're not changing the pixel density at all. We're just changing the overall dimensions of the image. So if I go ahead and put this back to the original 17.28 if you look down at the bottom here, you can see this re sample option now. We haven't actually looked at this yet, but when you're re sizing the image here, you can either leave it in automatic and let Photoshopped decide what to do. So you can see if you open up the drop down menu that there's additional, more advanced options if you choose to use them and they are labeled for enlargements or reductions. But if we go ahead and turn this off, you'll notice that the width and the height are now joined with the resolution, whereas before they were not. This is called re sampling an image. So what you're going to see here is we've got the width and the height. I'm gonna go ahead and reduce that again down to 11 by seven. There you'll notice that the resolution increased. If I go ahead and change this to something higher like 25 inches, you'll see that the resolution has dropped again. When you're trying to make images bigger, it doesn't matter if you're re sampling or re sizing. Either way, it's a bad idea because you're gonna end up with a less quality image. It's always when you're going from larger to smaller that you're gonna have great results. So this is why you always keep the raw files or the highest quality files that you have for images in case you need them later for another use. So as you can see when you're dealing with resolutions and everything, images can become quite complicated quite quickly, but especially when you're starting out. If you remember that a good high resolution image at 300 peopie I is good for print and a 72 PP. I image is good for the Web. When sized properly, then you'll at least have a good base start to go from, and you'll be able to add to your learning from there. 12. Megapixels: Normally, when people are talking about megapixels, they're usually doing it in reference to a camera. My camera is eight megapixels. My cameras, 10 megapixels. So what does that mean exactly? What is a mega pixel? Well, a megapixel is just a 1,000,000 pixels, and depending on the camera that you have, you're gonna have a different level of megapixels. Now, if we take a look at some of the megapixel options here, let's look at this image here. That's 16 megapixels. So it's almost 5000 by 3300 and size almost. And if we printed this image, we could print it up to 16.4 by 10.8. That's quite the large print, and this is where people tend to get confused about megapixels. You always hear people talking about how they need the latest camera with the most megapixels, and then you take a look at what they're doing with their photos, and all they're doing is posting them online. So if all you do is post your photos to Instagram and Facebook and flicker and those type of things and you don't print out your images, then megapixels really don't matter to you all that much. It's only when that you actually print, um, isn't going to matter. So, for instance, 16 megapixel camera here we could print 16 by 10. Almost a 12 megapixel camera again reduces the physical dimensions on screen as well as the print size. 10 megapixels were down to ah, 13 by 90 Most eight megapixel were down to almost 10 by 86 Megapixel were down to 10 by seven four megapixel were it eat by five and a three megapixel. We're looking at almost seven by five. If you wanted to print an image at five by seven, you're gonna need at least three or four megapixels. It's only when you want to print larger that you're going to need an image that's capable of being printed at that sides. Now, if you're going to be buying a new digital camera, another thing that you have to consider is the P P I. Because some digital cameras, even though they shoot three or four megapixels, are only shooting at 72 PP. I you generally have to buy a higher end camera to see IRA resolutions like that, but a lot of the base cameras now are even coming with something like 100 80 PP I to start out. So it's not 72 pp I, but it's still better for printing if you want to print something. So the next time somebody starts talking about megapixels, keep in mind that they're most likely referring to a camera doesn't really have much to do with print or the on screen version. When it comes to making graphics or creating graphics, it really has to do on what size of image you're gonna end up with on your camera afterwards. 13. Retina Graphics: Unless you've been living under a rock in the past couple of years, you've probably heard the term retina display. Now, technically, this is an apple term for their high resolution displays on their phones and their laptops . But in reality, a retina display is pretty much any display with a higher pixel ratio. So if we take a look at this example on Apple's website that shows the retina display here , we can see. On the left hand side is a standard 13 inch MacBook pro, and on the right hand side is one with the retina display so we can see on the left hand side that the text is, Ah, fuzzier. Um, it's not as easy to read when you zoom in on it, and the same goes for the images. Well, if I go down here, you can see that there's more blocking this in the image. Where's one on the right is a lot clear. If I go more into some of this wave here, you can definitely see the blocky edges down here, whereas on the retina screen it's ah, it looks a lot nicer now when it comes to these retina graphics, obviously you're going to be viewing them on a screen. Otherwise, it wouldn't be a retina graphic for a Britain a screen. So I want to give you an example of how this would work. So on that apple site we just took a look at, we could see that on the retina screen, even though the image was the same. Size is the one that was not a retina screen. It was a crisper and clearer image. So here's how they do that. So let's take a look at this image here. This is a standard 300 by 200 pixel image, and it's a J pig, and this would display fine on non retina screens. Now if we wanted to do a higher resolution retina screen at two times what we would do is we would create the image at 600 by 400 name it at two X. But when displayed on the website, it would actually display at the 300 by 200. If we did this at three times, it would be 900 by 600 for the image, and then it would scale down to the 300 by 200 So when it's displayed on the device, it's still displaying at 300 by 200. But all the extra pixels from the larger size are essentially being crammed down into that smaller space. Now, before retina screens came along, it was really bad practice to use a larger image and then just use HTML or CSS to size it down. But when you're dealing with these retina screens, if you want the image to look nice and crisp and clean on those higher resolution screens, you'll want to use the at two X and at three X images, depending on what that higher resolution is. It's a possibility that we could see even higher resolution images than this in the future . It's hard to say right now, so that's the gist of retina graphics and how you would go about creating retina graphics for use on the Web. 14. Google Images: Due Diligence: I want to take just a moment to talk about Google images. So a lot of people these days, if they need some kind of picture for their graphic design work, the first thing that they're gonna do come to Google type in what they're looking for. Let's go with cat pictures because cats are really popular and we see a bunch images here, and we can just click on the images tab, which gives us a whole bunch of images to choose from. Now, the common misperception is that you can use these images for whatever you want for whatever purpose, and that is not the case. If you're using Google images to search for pictures, there is a potential that you could use them. But it is your obligation to do the due diligence to find the copyright holder of that image, to request permission and pay any licensing fees required to use that image. It doesn't matter if you're a tiny little doctor's office putting out, you know, a couple of little flyers or your a big corporation. This is not a free for all to steal images off the Web. All these images have some kind of copyright attached to them. And Google just gives you an easy way to source these images. It's still up to you to find out the cooperate holders and painting licensing agreements. Copyright holders. Thank you for this. 15. Outro: Well, that's it. You've survived to the end. Thank you for taking my course. Understanding images. We've covered a lot of different topics. And I hope you learned a lot. Have fun and keep on learning.