- [Voiceover] In this movie, I'll show you how to auto-trace
an image inside Illustrator.
And I'll also show you the effects of resolution
on the quality of the results.
And the very short story there is more resolution is better.
So the first thing I'm gonna do is click on my image
with the black arrow tool in order to select it.
Notice we can see the resolution up here
in the control panel.
Ppi stands for pixels per inch.
300 tells us that we have 300 pixels per inch,
both horizontally, as well as vertically.
Which means 90,000 pixels per square inch.
Which is your typical professional quality print resolution.
Alright, I'm gonna need a copy of this guy
for demonstration purposes,
so I'll go up to the edit menu and choose the copy command,
or of course, you can press control + c
or command + c on a Mac.
Next, notice this image trace button right there.
If you click on the down-pointing arrow head next to it,
you'll see a menu of presets.
If you're tracing a photograph and you want color,
then you can try out one of these first two guys.
The next ones trace low-color images including
just shades of gray.
If you drop down to line art and technical drawing,
which would seem like the best settings, just know that
they trace stroked outlines.
Which may turn out to be what you want, and I am going to
include a movie about that inside this chapter,
but they're very slow.
For this kind of artwork, you want one of the
black and white options, which will trace
filled path outlines, and so you could try
black and white logo, sketched art, or silhouettes.
Or better still, just go ahead and click on the
image trace button and let Illustrator do it's thing.
Now, at this point it's going to warn you that
it's going to take a moment or two to trace the artwork.
And that's because we have a large image, meaning that
it contains a lot of pixels.
If you want to reduce the image size, you can rasterize it
to a lower resolution using the rasterize command
under the object menu.
I'll show you what that looks like in just a moment,
but this is terrible advice as you're about to see.
So I'm just going to go ahead and click okay in order
to trace the artwork.
It is going to take a moment, and you may see
a few progress bars, after which point you'll see
the traced version of the artwork.
Which isn't gonna look nun too good at this point.
We're gonna make it look much better in future movies.
But let's see how that compares to tracing a low resolution
version of the image as Illustrator just recommended.
I'll go ahead and press control + f, or command + f on a Mac
in order to paste a copy of the original pixel-based image.
And then I'm gonna twirl open this tracing layer here
inside the layers panel, and I'm gonna rename this guy,
the new one, 72 ppi.
And then, to lower the resolution of the artwork,
I'll go up to the object menu
and choose the rasterize command.
And I'll leave the color model set to RGB.
And I'll set the resolution to screen, 72 ppi.
The other settings really don't matter for our purpose.
So I'll go ahead and click okay in order to reduce
the resolution of that image.
And you can see the difference.
This is the before version, which is pretty sharp,
and this is the after version, which is pretty darn choppy.
Alright, let's see what kind of difference that
makes for image tracing.
I'll once again go up to the image trace button
and just click on it.
Notice this time Illustrator doesn't complain
and it's lickety-split fast,
but it looks absolutely terrible.
So this is the 300 ppi resolution version of the image.
And this is the 72 ppi.
And so the moral of the story is
you always want more pixels, not fewer.
It is going to take Illustrator a little additional time
in order to perform the trace, but it's gonna give you
better results as well.
And notice now by the way, that Illustrator has gone ahead
and renamed these objects image tracing.
I want to remember their original resolution,
so I'm gonna change the bottom one to 300 ppi,
and I'm gonna rename the top guy 72 ppi.
And then I'm gonna change their order as well
so the better tracing is on top.
And that's how you perform a first-pass auto tracing,
preferably on a high resolution image
here inside Illustrator.