Tutorial time!
Well, not really a "tutorial," per se, as I'm not guiding you through anything. And there's no pictures. (Did I just lose half my remaining audience?) Herein, I babble a lot about image resolution.
A lot of people misuse DPI, and many times it's not their fault. This is a quick intro on what DPI means, and how it affects your images.
DPI stands for "dots per inch," and it's a measure of resolution. If you're lost already, grab a newspaper and look at a photo printed there. Look really, really closely. You'll see how it has lots of little dots making it up--not smooth lines or even shading, just lots of dots in varying concentrations. If you counted all the dots in one square inch, you'd have the DPI measurement of that photo. But don't do that. I mean, unless you're really bored.
As this Wikipedia article explains nicely, a lot of people on the internet use DPI to refer to the resolution of digital art. For familiarity, this is what I'm going to be referring to--resolution in digital form. (What this means is that I'll be using the term "DPI" because everyone's used to it, even if it's not technically correct, and should probably be called "PPI." This is similar to using "megabyte" because everyone knows what that is, when what you really mean is "mebibyte.")
When you scan something in, it's best to scan it at a high DPI--150 or even 300 if your computer can handle it. (An image at 300 DPI can be quite a large file, so a slower computer might not open it easily.) For instance, when I want to scan in one of my silly pieces of linework art, I scan it at 300. I do all my "artistic" work at 300, because you can get quite a lot of detail in that way.
But when you work at a high resolution like that, you have to be aware of the difference between the size in actual pixels and the size it'll print at. In Photoshop (I use 7, but it's been like this as far as I can recall), under View, you can choose Actual Pixels. This can be deceptive if you have a high resolution of your picture. To see what it will print at, choose View > Print Size. If you have your resolution set high, you'll see your picture shrink!
So you want to have a lower resolution. For the web, the generally accepted standard is 72 DPI. Some photo sites will display their images at a slightly higher resolution--90-some, I think. I like 72 DPI because the Actual Pixel size and the Print Size are the same. Much less confusing. Never ever make it smaller than 72 DPI, because then you're sacrificing too much quality, and being confusing to boot. Secretly, everyone expects to have a nice, comfortable, 72 DPI image to look at and download and love.
And as a last note--in Photoshop, to set your resolution, go to Image > Image Size. There's a box in the window that comes up for you to fill in the resolution. Changing the resolution will change the Pixel Dimensions, too, but you can fiddle with the height and width after you set the resolution. To a degree, that is--you don't want to make it bigger than it was to start with. You can resize something to make it smaller fairly well, but making it bigger (and having it look good, of course) is much more difficult.
(Maybe someone could comment with the exact method to change resolution/image size in PSP, because it turns out my copy is defunct, woops.)
Anything still confusing? Did I say something stupid? Comment and tell me how I messed up! =D
Ooh, Blade is on! Time to watch Wesley Snipes pretend to be cool.
A lot of people misuse DPI, and many times it's not their fault. This is a quick intro on what DPI means, and how it affects your images.
DPI stands for "dots per inch," and it's a measure of resolution. If you're lost already, grab a newspaper and look at a photo printed there. Look really, really closely. You'll see how it has lots of little dots making it up--not smooth lines or even shading, just lots of dots in varying concentrations. If you counted all the dots in one square inch, you'd have the DPI measurement of that photo. But don't do that. I mean, unless you're really bored.
As this Wikipedia article explains nicely, a lot of people on the internet use DPI to refer to the resolution of digital art. For familiarity, this is what I'm going to be referring to--resolution in digital form. (What this means is that I'll be using the term "DPI" because everyone's used to it, even if it's not technically correct, and should probably be called "PPI." This is similar to using "megabyte" because everyone knows what that is, when what you really mean is "mebibyte.")
When you scan something in, it's best to scan it at a high DPI--150 or even 300 if your computer can handle it. (An image at 300 DPI can be quite a large file, so a slower computer might not open it easily.) For instance, when I want to scan in one of my silly pieces of linework art, I scan it at 300. I do all my "artistic" work at 300, because you can get quite a lot of detail in that way.
But when you work at a high resolution like that, you have to be aware of the difference between the size in actual pixels and the size it'll print at. In Photoshop (I use 7, but it's been like this as far as I can recall), under View, you can choose Actual Pixels. This can be deceptive if you have a high resolution of your picture. To see what it will print at, choose View > Print Size. If you have your resolution set high, you'll see your picture shrink!
So you want to have a lower resolution. For the web, the generally accepted standard is 72 DPI. Some photo sites will display their images at a slightly higher resolution--90-some, I think. I like 72 DPI because the Actual Pixel size and the Print Size are the same. Much less confusing. Never ever make it smaller than 72 DPI, because then you're sacrificing too much quality, and being confusing to boot. Secretly, everyone expects to have a nice, comfortable, 72 DPI image to look at and download and love.
And as a last note--in Photoshop, to set your resolution, go to Image > Image Size. There's a box in the window that comes up for you to fill in the resolution. Changing the resolution will change the Pixel Dimensions, too, but you can fiddle with the height and width after you set the resolution. To a degree, that is--you don't want to make it bigger than it was to start with. You can resize something to make it smaller fairly well, but making it bigger (and having it look good, of course) is much more difficult.
(Maybe someone could comment with the exact method to change resolution/image size in PSP, because it turns out my copy is defunct, woops.)
Anything still confusing? Did I say something stupid? Comment and tell me how I messed up! =D
Ooh, Blade is on! Time to watch Wesley Snipes pretend to be cool.