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Hi, I'm Paul Kaiser. Let's talk about the difference between Bitmap and Vector graphics.
Bitmap graphics are kind of like working with a large piece of graph paper. Here we are, we've
got all these different squares, they're all the same size, lined up in rows and columns, and each
one of these is called a pixel. Well, each one can have its own color. And when we do that --
color each one individually -- we can end up with a nice image. This is working with Bitmap
graphics. Vector graphics don't use pixels. Instead, they use paths. This line that you see
here that I'm tracing, this is a path, and so what we do with Vector graphics is define those
paths, which go between points. So we have points, and between them we have paths. And we
define how those paths are shaped between points with these tool handles here. Behind the
scenes, the program is keeping track of this with a mathematical equation, and
that's what's stored for our Vector graphic. So, we're not talking about pixels, we're just
talking about paths and the shape of the path. An important difference between Bitmap and
Vector graphics is how they're stored and their resulting file size. We said that in Bitmap
graphics there are all these pixels. Well, a Bitmap graphic generally stores the number of
pixels wide in the image, number of pixels in the image, and then it has to store a color value
for each and every pixel in the image. That can result in a lot of information and a pretty good
size file. For Vector images, the files are stored completely different. All that's saved,
generally, is information about each point, where it's at in relation to other points, and
then information about the path between points, how long are these handles, which direction
are they pointing, and that's about it. As a result, Vector graphics can be pretty small
files. Bitmap files and Vector files are usually saved in different types of files. Your
Bitmap most common file formats are BMP, your GIF, your JPEG, your PNG, and your TIFF. Those
are, generally, your most common Bitmap file types. For Vector graphics, your most common types
are usually AI, which is Illustrator format, EPS, and SVG. There are other types out
there -- there are plenty -- but these are the three most common ones you're going to find today.
You can't talk about Bitmap and Vector graphics without talking about resolution and detail. In
Bitmap graphics, the resolution refers to how much detail is in the image, and directly affects
the quality of the output. So here I have a low resolution image. You can see there's not
much detail, there are a lot of little jagged edges, that sort of thing. So this is a lower
resolution, and it's not going to print very well. Here's a higher resolution version of the
same shot. As you see here I've got a lot more detail, a lot crisper edges, that sort of
thing, and this is going to print great. When we talk about detail, this is like the
difference between a 5 megapixel digital camera shot and a 1 megapixel digital camera shot.
The lower megapixel is less detail. You're going to be able to do less with that image. With
a higher detail image, we can take that detail and spread it over a larger area. We could
print, perhaps, a large poster out of this image, whereas the other lower resolution image we
might be able to print a postage stamp and that's about it. A lot of times, when people are asked
to provide a higher resolution image, they make the mistake of thinking they can do that by
making a simple change in their image editing program. If I go in and say Well, I'll just
change the resolution up to 600. I'll just double it, and it will be great. Well, the problem with
that is, you didn't actually capture any more detail. When you made that resolution higher,
the program just worked with the detail it had, made some average calculations, and added some
more pixels around it. As you can see, it's still fuzzy. There's not really any more
detail captured. So, if you need more detail, you have to actually go out and retake your
digital camera photo at a higher resolution, or you need to put your photograph maybe on your
desktop computer scanner and scan it again at a higher resolution. Well, what about
Vector graphics when we're talking about detail here? We said that Vector graphics were
not dependent on pixels, it's dependent on these paths instead. Well, check it out. I
can zoom in, increasing the size of this image a ridiculous amount, and I'm not really
losing any detail around this edge. What happen is, this mathematical curve is
recalculated every time I size it up or down. The only limitation when it comes to
detail with a Vector graphic is the output device. In this when we're doing this screencast, our
output device is the computer monitor. But your output device could also be a 300 dpi laser
printer. 300 dots per inch. That's not really that high of resolution. Or, it could be a
1200 dots per inch laser printer -- a lot more detail there. Or, it could be a 2500 dot per inch
filmsetter, for printing a coffee table book or something really high quality. So, this
same graphic, this same Vector graphic can be output on all those devices, and the higher
performing device is going to make use of all of its pixels to give us a nice, smooth curve.
Well, we've really made it sound like Vector graphics are the way to go, with their small file
size and their fact that you're not limited with detail. But, let's have a look at a nice
bitmap image here, in Photoshop, this is an image of a wedding dress that has a lot of detail
in here, and a lot of subtle tone variation in the skin, that sort of thing. Now, because it's
a Bitmap graphic, we can set the color of each individual pixel independently and get this nice
smooth continuous tone. Well, we can't really do that with a Vector graphic. Remember, Vector
graphics are built of paths, and each path can have a color, and it can have a fill on the
inside. But here's what it looks like when we try to make that same wedding dress in
Illustrator. Now, you might be looking for this stylized effect, but if you really want a
photograph, Vector graphics are not the way to go. Well, what's a good use for Vector graphics,
then? Well, look at these logos. These logos might be used on business cards, or they might be
used on billboards. Remember, we talked about Vector graphics not really having limitations on the
detail based on the size. So, you could take the same little logo here, put it on a little
business card, then blow it up and put it on a billboard, and not lose any detail from the
Vector graphic. As you're learning to work with graphics, if you just stick to Bitmap
images for your photographs, and then use Vector graphics for your logos, that sort of
artwork, you'll be just fine. I hope you've enjoyed this little introduction, and I hope that
you'll see more tutorials in the near future about working specifically with Bitmap
graphics and working specifically with Vector graphics.