Photoshop_User_June_2017

> PHOTOSHOP USER

>^ JUNE 2017

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Original

Expanded Original Squeezed

© Scott Valentine

Linear grad D-map and result

© Adobe Stock/Alexander Y

from bottom to top. The third channel is not used, which is why it’s

blue. (Ha ha! Well, I thought it was funny.) Anyway, use the Blue

channel to make notes or sketch boundaries when you get to really

detailed D-maps, but for now we’ll ignore it.

There’s an interesting gotcha using channels, though. Remember

that channels get blended together, so if you paint with pure RGB red

on a regular layer, the Red channel gets pure white, but the Green and

Blue channels get black, and that will affect our D-map! The way around

this is to work directly on each channel independently. If I open a docu-

ment with a single layer filled with 50% gray (see images above), I can

go directly to the Red channel and apply a black to white linear gradient

from right to left, and on the Green channel from bottom to top. The

result will look expanded. Reversing that causes everything to squish.

CREATING THE DISPERSION EFFECT

We now have everything we need to start making a dispersion effect.

I’m using this dancer from Adobe Stock because it has a relatively uni-

form background and will make things much easier to see. To obtain

the stock image used in this exercise so you can follow along, add

it directly to your Libraries panel (Window>Libraries) by clicking on

the link for the image on the next page. When the Adobe Stock

webpage opens, make sure you’re logged in to your Adobe account,

then to the right of the image, you’ll see the option to Save Preview to

My Library (you can click on My Library to select a different library or