Profesional Selections

7/31/2019 Profesional Selections

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Contents

Intro to Channel Selections 2

Making a Channel Selection 3

He ps an Hints 5

Using Extract 6

C anne s Pa ette Exp aine 8

Advanced Selections


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Channels represent a few different things. First and foremost they

represent the colors that are in your image. These are typically

represented by red, green and blue channels (RGB) or by cyan,

magenta, yellow, and black channels (CMYK). All images have

a composite channel as well. This is the channel youre viewing

when you are working on your image.

Channels can also be used to save selections. Try this to see how

it works:

1. pen any image. Make a simple selection with your marquee

too .

2. Open the Channels palette and click the new channel icon at

the bottom of the palette.

3. Click on the new channel that was made (probably named

Alpha 1). Note that where the selection was is solid white,

and everything else is black. This is how the Channels palette

saves selections. It makes a channel where white is the

selected area, and black represents the areas that are not

part of the selection.

4. Deselect (com-D; PC cntl-D) so there is no selection. Click

n the channel that says RGB or CMYK. You should see thefull color image again. Theres no selection on. To reload the

selection you just made, hold down the command key (PC:

ontrol) and click on the new channel at the bottom of the

hannels palette. Your selection reappears.

The Channel Advantage

As you go through this tutorial, youll likely be comparing it in

your min to ot er ways o se ecting t ings. e a vantages to

using c anne s are a un ant.

First, you can use a channel the same way you use quickmask.

The difference is that when youre viewing a channel as a

quickmask, you can actually hit save to save your document and

your channel along with it. If youre in the middle of a complex

selection in quickmask mode there is no way to save your work.

Second, if you start out with a color channel as your saved

selection can do anything to a channel (or a Layer Mask if you

choose to follow Help/Hint #2) that you can do to a Grayscaleimage. This can give you a great head start.

Third, using an existing color channel as a starting place for

a selection allows you to follow the edges of the photographic

information instead of clipping along an image visually and

hoping its good enough.

IntrotoChanne

Seections

Ex. 1-2.Duplicate the channelwith the most contrast

Ex. 3.Duplicate the channelwith the most contrast


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graphicauthority.com

3

MakingaChannelSelection

Now that you understand how channels representselections,

the rest of this kit will provide you with methods of using black

and white channels to makeselections.

1. pen a p oto rom your ar rive. Go to Har Drive >Applications > Adobe Photoshop CS > Samples > Palm Tree

(CMYK).tif. (PC: Go to My Computer > C Drive > Program

files > Adobe > Photoshop CS > Samples > Palm Tree

(CMYK).tif)

2. Look at each of the RGB or CMYK channels individually.

Choose the one with the greatest black and white contrast

etween t e o ject you nee to se ect an t e ackgroun .

Duplicate this channel by dragging it to the new channel

icon at the bottom of the Channels palette. In this case it is

bviously the Yellow channel.

3. The object to be selected needs to end up white in the

hannel and the background needs to end up black. If

the object is darker than the background, (as it is in our

xample) you will need to invert the black and white. Go to

Image>Adjustments>Invert (com-I; PC cntl-I).

4. Choose the Burn tool in the Tools palette (nested under the

Dodge tool). Choose a relatively large, soft brush. In the

ptions bar, choose Shadows for the Range and change the

Exposure to 20%. Now darken the outside of the object with

t e Burn too . Go aroun t e e ges once or twice. Dont

worry a out getting a so i ack out ine yet.

5. Choose the Dodge tool. Use the same brush. In the Options

bar, choose Highlights for the Range and change the

Exposure to 20%. Now lighten the inside of the object with

the Dodge tool.

6. Go back and forth between dodging the inside and burning

the outside until you have the black and white edgesof a

silhouette. Try to keep the edge of the silhouette soft. Avoid

hard-edged transitions. The key is to keep the brush the right

size and avoid going directly over the edge with the center of

the brush.

Ex. 2.Duplicate the channelwith the most contrast

Ex. 3-6.Invert if necessary, thenbegin to o ge an burn.


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MakingaChanneS

eection

7. ere wi e areas t at were misse y t e o ging an

burning. These you will paint over with the Brush tool and

100% black or white. Paint the inside of the silhouette white.

Paint the outside black. Avoid touching the edges of the

silhouette with the paintbrush. If any touch up is necessary,

use a small brush to clean up (i.e. areas where the Dodge

and Burn tools didnt make the right edge). You only need to

Dodge and Burn the edges of the silhouette. Once you have

a nice black area around the outside, paint the rest of the

background black. Do the same with white on the inside of

the image.

8. Go back to your composite RGB or CMYK channel (com-~;

PC cntl-~). Then make a selection out of the new channelyou just made by command-clicking the channel in the

hannels palette (PC cntl-click). Youre ready to make a

mask from the selection, or drag it to another image!Ex. 7. C ean up until all that isleft is a silhouette on blac .


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ssoTool

Hints and Helps with Making Selections from

Existing Channels

When creating a channel specifically for making a selection,

often times you may lose yourself in the process and wonder justhow good your selection is going to be. Here are a couple of tips

for checking your work.

He p Hint #1

If you want to see how your channel is matching up to the

original photo, click the Show icon (eyeball) in front of your

composite channel. This makes the Alpha channel youre

working on show up as a red overlay on top of your image. You

can actually work this way, or turn the eyeball off again and

continue on in black and white.

Help/Hint #2

If you want to work on the image itself (cutting it out as you

Dodge and Burn) try this:

1. ommand-click (PC: cntl-click) on the channel youve been

using for your selection.

2. Click on the composite channel and go back to your Layers

palette. If your image is on the Background layer, youll need

to double click the layer in the Layers palette and click OK.

Then click the New Mask icon at the bottom of the layers

palette. This makes a mask out of your selection.

3. Now you can Dodge on top of the image to make more of itappear, and Burn around the image to make the background

isappear. This allows you to work visually.

He p/Hint 1 View your channelli e Quic mas Mo e.

Help/Hint 2.Dodge and Burnon a Layer Mask to see your

results live


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UsingExtract

1. pen a p oto rom your ar rive. Go to Har Drive >

App ications > A o e P otos op CS > Samp es > Eag e.ps .

(PC: Go to My Computer > C Drive > Program files > Adobe

> Photoshop CS > Samples > Eagle.psd). Duplicate the

layer that has the object(s) to be extracted.

2. Go to Filter>Extract or type com-opt-X (PC cntl-alt-X).

3. Use the Highlighter tool to determine where the edgesof the selection need to be. Then use the Paint Buckettoo an c ic on t e insi e of t e se ection.

4. Click Preview to see how your first round went. If youneed to adjust your edges turn the Preview settings

back to the defaults (at right).

5. Use the Eraser and the Highlighter to adjust the greenhighlight. The rule here is that you want a thin line

where the edge is sharp and in focus, and a fatter linewhere the edge blurs into the background. Frizzy hairmight be mostly green highlight, while the sharp lineof someones skin has a thin highlight.

6. Once youve a juste your ig ig t, c ange your

settings back to the preview settings shown at right.Repeat these steps until your preview shows you what

you want to see. Then Click OK.

Ex. 1. Open an image. We usedone that comes with Photoshop.

Ex. 3-5.A tolerance of 0 will selectonly the exact color you click on


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UsingExtract

ou wont see any ifference at first, ecause youduplicated the layer and the two on top of eachother dont look any different.

7. Command-click (PC cntl-click) on theig ig te ayer in t e Layers pa ette.

8. Go to the original layer and click the New LayerMask icon at the bottom of the Layers palette.

9. Delete the duplicate layer that does not have alayer mask.

Ex. 7-8. Use the extracted image asa selection and make a mask on

the original.

Ex. 9. Voile!


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AClick to show or hide a channel

B. The top channel of most files is the compositechannel. Press ~ to show the compositebehind an alpha channel without activating thecomposite

C Color Channel. Shift-click to activate/deac-tivate. RGB and CMYK files are made up ofchannels representing each individual color

D A layer mask is represented as a channel also

E An alpha channel is a saved selection. Use thekey command listed on the channel to viewit. Add option (PC: alt) to make it a selection.Double-click for Channel options

F Load Channel as selection

G Save Selection as Channel. Option-click (PC:alt-click) to bring up options

H Create New Channel. Command-click (PC:cntl-click) to create a Spot Color channel

I Trash

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B

C

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F G H I

ChannesPaetteExpained

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