Photoshop 02

Representation of color RGB//Hue Saturation Brightness

RGB

from wikimedia

r, g, b: (in 8 bit/channel)

255, 0, 0: red
128, 0, 0
64, 0, 0

0, 255, 0: green
0, 128, 0
0, 64, 0

0, 0, 255: blue
0, 0, 128
0, 0, 64

255, 0, 255: magenta
0, 255, 255: cyan
255, 255, 0: yellow

128, 128, 128:
64, 64, 64

0, 0, 0

Hue Saturation Brightnesss

from http://www.handprint.com/HP/WCL/color7.html

from https://en.wikipedia.org/wiki/Munsell_color_system

Notes

Color picker Hue/Sat tool

Hue selected

Saturation selected

Brightness selected

Notes

Hue Sat Adjustment (without masks)

With masks

Targetted Adjustment with ranges

Use the hand tool to select target color

drag hand (sideway): changes the saturation of area
cmd+drag hand: changes hue of area

Notice that when you drag, the dropdown menu automatically goes to the colors (yellows, blues...etc)

Notes

Curves

Can do everything Levels, Brightness/Contrast, Color balance can, and more. (In the old days, it was said that if you master curves you won't need most of the tools in adjustment menu.
- checkout Presets
- "S" curve: increases contrast
- reverse "S" curve: reduces contrast
- Click on image to see where it corresponds on curve.
- Option-Click to create point.
- Red, Gree, Blue chanels!!

Notes

Color mixing/Channels

Notes

RGB channel

Open a fully colored image in photoshop
Make sure only the colored original photo is highlighted in the layers panel.
Go to the Channels panel. (To make the thumbnail larger, right click and choose size)

Click and choose one channel to isolate r or g or b
- You'll see a b/w image. This is the intesity of red, green, or blue light
- White: Value 255 of that colored light
- Black: 0 of that colored light
- Gray: in between
Cmd-click on b/w image thumbnail on channel to select.

Marching ants only encircle the pixels you are selecting more than 50%. But in fact, you are selecting ALL based on intensity.
White area -- you are selecting 100%, black area you are selecting 0%, and gray in between

With the selection active, go back to layers panel, make Solid Color that matches the color channel you selected

Repeat this for red, green, and blue so that you have three solid colors with the mask made from the appropriate channel

Make a black solid color and put it under neath the red green blue layer and turn the original color image off.
Turn the blending mode of the red, green, blue solid color layer to "screen"

You should have the full colored image back!!!

Notes

Color from B/W

Instructions!!
Past student work

Notes

Extra Review Materials

Notes

Adjustment Layer + Layer Mask = Local Corrections

Layer masks

Original Image (right side too dark)
Brighten the image With adjustment layer
Adjustment layer with layer mask

Notes

Clipping Mask

Right-click on the adjustment layer and select "Create Clipping Mask". Then the adjustment layer will only apply to the layer immediately below it.

Notes

Selection to Layer Mask (Adjustment Layers)

1. With selection (Marching ants), create new adjustment layer

2. selection automatically converted to layer mask

Notes

Flattening Image

Once you are done and ready to commit:

save the layered version file (un-flattened) as a PSD
save the flattened (commited) version as a TIFF
- pulldown menu on the top right corner of the layers panel -> Flatten Image
- or, Layer -> Flatten Image

Background layer

When you open an image, Photshop puts it in a layer called Background, which has restrictions (as represented by the lock sign).
If you want to unlock and modify the background layer and treat it as a normal layer, double click and make it into Layer 0a

Notes