Now that we've got a good foundation of image and display resolution,

let's take a look at a more traditional method to view images, print.

When browsing the web, we often see images that appear high quality and look great.

However, I'm sure everyone has seen just the opposite

when you've gone to print that high quality image.

Perhaps it's smaller than you thought.

Perhaps it's blurry or chunky.

When we print something, we have to work with ink and

need to translate pixels into something else, dots.

A single pixel's illuminated on a screen with subpixels, which give us the colors.

These subpixels emit a combination of red, green, and blue light, or RGB.

Similar to a pixel, a dot on paper is made up of colors, but

that's where the similarities end.

A combination of ink spots in the colors of cyan, magenta, yellow, and

black, or CMYK, are used to replicate colors.

The shape of a dot is slightly different and depends on the type or

printing technique being used.

We won't get into all the nitty-gritty details here but,

as we can see already, the transition from screen to paper is quite different.

The quality of a printed image depends on, one, the image resolution, or

pixel density.

And two, the capabilities of the printer.

The pixel density of images, or PPI,

has a cousin in the offset printing world, dots per inch, or DPI.

Offset printing is a process typically used by printing press companies

that transfers each color in a graphic file into individual plates.

Then the plates are used to imprint each color onto a sheet of paper.

Now I'm gonna stop here for a minute, PPI and DPI are often used interchangeably.

Generally, we'll use PPI since we're working with pixels first in

our applications.

DPI is mostly concern for a print shop, where you may take your design to be

professionally printed on an offset printing press.

It's still an important consideration, but for

most purposes of creators today, we can think in PPI.

So I'm gonna continue using PPI in this course.

Now let's take a look at what goes into making a quality print and

how PPI affects our printed graphic.

So let's take a look at our LCD monitor again.

Remember, this display is running at a resolution of 1920 by 1080.

LCD display pixel density is typically somewhere between 67 and 130 ppi.

We're not able to increase or

decrease the size of an individual pixel on the display.

So generally we see images with a default ppi of 72.

However, if this number is different and you're designing something for

the web or an app, that's okay.

Remember pixel density, or

ppi, won't affect the quality of the image on a display.

Now when we print out this creation

we need to tell the printer the size of the pixel to print as a dot.

When we increase the ppi, we actually decrease the size in inches of the image.

However, it should result in a higher density printed image.

If we decrease the ppi, we actually increase the printed size.

Say, 10 pixels per inch would result in a huge print.

So let's see an example.

Here we have an image that is 300 pixels by 300 pixels and

currently set to 100 ppi, resulting in a printed image of 3" x 3".

If we increase the ppi to 300, the printed image will result in a 1" x 1" graphic.

And the opposite, 10 ppi would result in a larger 30" x 30" printed graphic.

And just to drive it home,

even though we've changed the ppi of the image it's still 300 pixels by 300 pixels.

Changing the ppi won't change the pixel value and how it shows up on our screen,

even if we're looking at a high density or retina display.

Here's a quick grid for reference.

Print and display.

Printed assets, and let's limit this to an 8 and a half by 11 sheet of paper,

should have an output ppi of about 150 for home printers.

For offset printing, 300 is a good number.

But I encourage you to reach out to your printer and work with them directly.

If you're printing photos, this should still apply.

But you can check with your vendor.

For color, ensure you've either started your graphic file in CMYK or

converted your photo into CMYK, to get the most accurate representation.

We'll get into this deeper in the next video.

For displays, we don't need to worry about ppi.

Most applications and images from devices use 72.

And that's fine, one less thing to worry about.

For our color we'll want to stick with RGB.

Hopefully, that gives you a base to work from and

the grid gives you a reference point.

In the next video, we'll take a brief dive into color and color spaces.