In this very simple tutorial I am using Adobe Illustrator (CS3) to show you how easy it is to get a nice gloss using the opacity mask. Start by creating a new 400 x 400px rgb document. I will use popular star (badge) shape that you can see a lot around telling you that something is new or so.

Step 1

Select the star tool and click on the blank canvas, for start use the following settings from the dialog.

Give your star a  fill of  k10 and a stroke of 0.5 and set the stroke color to k20 (k10 means 10% black). It should look like in the image below (click the image to see it in full size).

Step 2

Ok I’ll copy and paste this star. (Edit > Copy ) and paste it but it is better to use Edit>Paste in front since it will position the copy exactly over the first star. Now select the copied star and scale it down to 90 %. Go to menu Object>Transform>Scale and set it to 90%

Set the stroke of the scaled down star to none and fill it with red. It should look something like this

Step 3

Ok let’s edit smaller star’s fill. It will look much better if we fill it with gradient. Select the smaller red star and give it a simple gradient fill.

Ok now it looks much better with this linear and simple but effective gradient fill. Wait  we are talking about gloss here, right?

Step 4

In order to have nice gloss let’s take the pen tool and draw freely where we want our gloss to go, fill the pen made shape with linear gradient from white to black and set angle to -90 degrees.

Now select the shape that  we have just made and filled  with gradient and go to Transparency tab (If you don’t see it go to Window > Transparency) and change the blending mode from normal to screen. You will get something like this.

Yes we can see the gloss but what about those spills? That is why we need opacity mask.

Step 5

To get rid of spills select the first largest star and go Edit > Copy (ctrl+c) , we have it now on our clipboard, now select that shape that spills and go to Transparency tab and you will see something like this.

Double-click where it shows on the image (where the hand cursor is) and this black rectangle will appear.

Now click o that black field and go Edit > Paste in front (ctrl+f)  , remember that we copied that large star and now we pasted it in front. Have a look now, all the spills are gone and  we have a clear image and now it looks like this. Great !

Opacity masks are really cool and you can really do wonders with them so go ahead and try it you’ll see it is really easy.