Digital Skills for Visual Media

Image Editing:
Digital Color
V I S U A L M E D I A D E S I G N 10 5
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Visual Media Design 105 > Digital Skills for Visual Media
COLOR MODES: RGB & CMYK
Color can be a complex issue for computer users. There are many
variables and very few settings that can be considered universal.
Because of this, it is important to develop an understanding of
different color modes. Photoshop has four primary color modes
that you should be aware of.
Bitmap: Each pixel can have only 1 of 2 possible states: pure black
or pure white. Lineart [simple logos, type] is sometimes scanned
into this color space.
Grayscale: Each pixel can have one of 255 possible tonal values
ranging from white to gray to black. The grayscale color space is
used for simple 1 and 2 color offset print projects.
RGB: This is the color space of digital devices. Image assets for
interactive media must be converted to RGB. Each pixel in an RGB
fle is assigned a shade of Red, Green or Blue light. For each color,
there are 255 possible values.
RGB is additive color—colors are defned by varying amounts
of red, green, and blue light—100% of each of the three colors
produce white. An easy way to remember that RGB is additive
color is to remember that by adding more color the result is closer
to white. Because RGB color is transmissive, black is the absence
of light.
CMYK is the color model of offset printing, and describes the Cyan,
Magenta, Yellow and Black ink that is used in traditional 4-color
process printing.
Each pixel in a CMYK fle is assigned an intensity of Cyan, Magenta,
Yellow or Black ink.
CMYK is subtractive color—pigments absorb light waves of
particular colors and reflect light waves of other colors. In other
words, magenta ink absorbs (subtracts) all wavelengths of color
except magenta, which is reflected towards the viewers eye.
Subtractive color is reflective—black absorbs all wavelengths
of light.
The color wheel demonstrates the relationship between RGB and
CMYK color. Notice that cyan is opposite red. This means the two
colors are complements or opposites—pure cyan has absolutely no
red in it. When cyan is displayed on your monitor you are viewing
a color composed of 100% blue and green and no red. The same
relationship exists between blue and yellow, and green
and magenta.
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Visual Media Design 105 > Digital Skills for Visual Media
DEVICE DEPENDENCE
The two color models most commonly used by screen and print
designers are RGB and CMYK. Each of these color models are device
dependent: the same color description can vary from one device
to another. For example, an image printed in CMYK on an offset
press will look different from the same image output to a color laser
printer. The same image, in RGB, will look different on a website.
It is this device dependency that creates much of the frustration
surrounding computer-generated color images.
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Visual Media Design 105 > Digital Skills for Visual Media
PROJECT: THE COMPLETE PRINT WORKFLOW
Preparing assets for print or screen projects revolves around three
core fle properties: pixel count, color space and fle type. The
next two exercises put these three variables together and take
you through the process of preparing assets for print and screen
respectively.
Files optimized for print require enough resolution to reproduce
without looking pixelated. They must be in the CMYK color space,
and should be saved in an uncompressed fle format, usually TIF.
Scenario: You found an image online that you want to use in a flyer
for your work. The flyer will be printed commercially. Preparing this
fle will revisit each of these three core variables and optimize the
image for print.
GETTING STARTED
£ To get started, fnd and open the fle Hunter_Start.jpg.
This fle needs to be 7 inches wide at 300 PPI. You will also need to
convert the color space to CMYK, and change the fle type to TIFF.
ASSESS THE IMAGE
£ The document name in Photoshop shows you that both the
color space and fle type are NOT correct for print.
£ To assess the fle resolution, go to Image > Image Size. Change
the units in this dialogue to inches.
Interesting numbers: only 72 PPI, but the physical size is much
bigger than you need. You can use Image Size to compress the
pixels in this fle into a smaller physical size, thereby increasing the
resolution.
RESIZE THE IMAGE
£ Uncheck Resample Image and enter your target resolution, in
this case 300ppi.
£ Notice how the physical size of the fle (width and height)
changes dramatically when you do this, but that the fle size
and number of pixels stays the same.
£ Save the fle.
Note: if the numbers revealed that the fle was too small for your
project, your best bet would be to try to get a bigger fle from your
client. Upsampling is usually a recipe for disaster [and yelling]
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Visual Media Design 105 > Digital Skills for Visual Media
RESAMPLE THE IMAGE
The image width is still not right. You can use ImageSize to trim
away the extra pixels.
£ Jump back into Image > Image Size.
£ Recheck Resample Image and enter your target width, in this
case 7 inches.
£ Save the fle! The resolution and physical size is now perfect.
CONVERT COLOR SPACE AND FILETYPE
We need to do two more things to get the image ready for print.
£ First, go to Image > Mode > CMYK Color to change the color
mode of the fle. Notice the subtle color shift that occurs
when we switch color spaces.
£ Finally, we need to save the fle in an uncompressed format, in
this case TIFF. Choose File > Save As and chose TIFF from the
format popup menu in that dialog box.
£ Save your fle to the Desktop and name it like so: LastName_
Firstname_Print.tif.
£ Accept the default choices in the TIFF Options dialog box that
follows, although you should make sure that your document
is being saved in Macintosh format.
FINISH UP AND SUBMIT
£ Submit the fle to your instructor in the method that they
prefer. This may be to the class server or to Canvas. Ask your
instructor if you are unsure.
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Visual Media Design 105 > Digital Skills for Visual Media
PROJECT: THE COMPLETE SCREEN WORKFLOW
This project will take you through the steps required to prepare a
photographic image for a website or other screen design project.
Scenario: You have a layered Photoshop fle that you want to
upload to Instagram. You will need to flatten the layers, resize the
image, and change the fle format to JPEG. Let’s jump in!
GETTING STARTED
£ Navigate to the Exercise folder; fnd and open the fle Screen.
psd.
£ Always begin projects like this by assessing what you have
to work with, as we did in the previous exercise. In this case,
consider what you have now, and what you need for the fnal
fle.
FLATTEN AND DUPLICATE
First, make a flat copy of the fle in a way that will ensure that you
retain the layered version of the document.
£ Go to Image > Duplicate; check Duplicate Merged Layers to
create a flat copy.
£ Name your new fle LastName_FirstName_Screen and click
OK. You now have a flat copy of the original fle.
£ Now go to Layer > Flatten Image. In Photoshop, a fle is only
truly flat when it has only a locked Background layer.
£ Jump back to the layered fle and close it. ALWAYS keep your
native psd fles archived with a job: you never know when
you might need the originals!
RESIZE THE FILE
Instagram posts require square 1080 x 1080 pixel images. We’ll use
Canvas Size to resize the fle.
£ Go to Image > Image Size to see what you’re working with.
Close but not perfect.
£ Go to Image > Canvas Size. Change the units to pixels.
£ Enter 1080 for both width and height. Confgure the dialog to
Anchor the bottom part of the fle. You don’t want to cut off
the type!
£ Click OK and move on.
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Visual Media Design 105 > Digital Skills for Visual Media
SAVE A JPEG
Because your fle contains photographic imagery, you want to use
JPEG as the fle format.
£ Go to File > Save [Cmd-S] to save the document. Because you
made a Duplicate earlier, you are saving this fle for the frst
time.
£ Make sure the Desktop is the save location.
£ Choose JPEG as the format from the pop-up menu.
£ Click Save
JPEG OPTIONS
Part of saving fles for screen involves making decisions about how
much to compress the fle. The JPEG Options dialog gives you
control over this.
£ Under Format Options, choose “Baseline Optimized.” This is
almost always the best choice.
£ When you set the Quality there is a tradeoff between
compression and image quality. Try different settings and see
what happens to the fle size [in middle-right]
£ In this case, I would go with 8-12, as the image quality is
important and the fle is big. For smaller, less important fles,
you could push this setting lower for more compression.
£ Click OK.
FINISH UP AND SUBMIT
£ Submit the fle to your instructor in the method that they
prefer. This may be to the class server or to Canvas. Ask your
instructor if you are unsure.
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Visual Media Design 105 > Digital Skills for Visual Media
CHALLENGE PROJECT: CREATIVE COLOR
This exercise will explore a more creative way to think about and
use color in Photoshop. In this project, you will colorize a black and
white photograph using layers and special blending modes. The fle
you build here will be uniquely yours, and will put together much
of what you’ve learned about Photoshop so far in this course.
GETTING STARTED
£ Find and open the folder Colorize in the exercises folder. This
folder contains a few images that work well for a project like
this.
£ Choose the one you like best and open it in Photoshop.
£ The fle you just opened is a grayscale jpeg. First go to Image
> Mode > RGB Color. This changes the color mode of the fle
so that you can colorize it.
£ Now go to File > Save As.
£ Save a PSD fle to the Desktop as LastName-FirstnameColorize.psd. Now you’re ready for action.
CREATE LAYERS
This fle will use layers, the Paintbrush and the layer blending modes
to blend your colors with the detail in the original image.
£ Spend a few moments planning out your approach to the fle
and then create a few layers for each color you plan to use.
Part of the beauty of this fle will be the way you build it: each
color or object in the original image will require a different
layer.
£ Make at least fve separate empty layers in your fle
£ Give each layer names to describe the item that they will
colorize. Feel free to create more layers as you work through
the project.
£ Save your fle.
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Visual Media Design 105 > Digital Skills for Visual Media
DIGITAL PAINTING
Painting in Photoshop is just like painting with a real paintbrush.
£ Equip the Brush tool from the Photoshop Tool Panel, and use
the color picker to assign the foreground color you want to
use. Be sure the right layer is targeted before you paint!
£ Use the icons in the Options Bar to change your brush size
and edge properties.
£ Use the Color Panel to save colors for reuse in the project
£ Use the Eraser to fx mistakes and clean up your lines.
£ Save your fle after each major move you make
THE BLEND MODES
Photoshop has an elaborate system for visually blending layers
together called the Blending Modes. In this case, you will probably
get the best results by changing the blending mode of each of your
layers to Color. You can do this at any time during this project using
the popup menu in the Layers Panel.
MANAGE THOSE LAYERS
Once you have a painting worth framing, take a few moments to
manage the new layers you created.
£ First, be sure each layer has a descriptive name.
£ Then, select all the layers and type Cmd – G to place them
into a Layer Group. This is an easy way to organize the Layers
Panel and build Photoshop fles that are easy for you to
navigate.
FINISH UP AND SUBMIT
£ Review your fle and make sure that it’s perfect.
£ Submit the fle to your instructor in the method that they
prefer. This may be to the class server or to Canvas. Ask your
instructor if you are unsure.