Using opacity with type on a background image

Using Opacity with type on a background image

Software: Canvas 5
Platform: Mac OS and Windows

By using Canvas 5's channels and opacity controls, you can create the appearance of transparent type, in which a background image shows through the text characters. The effect is often emphasized by applying shadows and highlights to the type. In this case, we'll focus on the transparency effect. The How-to page on embossing into a background image describes how to create shadows and highlights.

Finished leaf image

By using Canvas 5's channels and opacity controls, you can create the appearance of transparent type, in which a background image shows through the text characters. The effect is often emphasized by applying shadows and highlights to the type. In this case, we'll focus on the transparency effect. The How-to page on embossing into a background image describes how to create shadows and highlights.

TIP: When you work with type and images, it's a good idea to convert text to objects. To do that, select your text object and choose Path >Convert to Paths in the Object menu.

To create the "Green Leaf Nursery" graphic, artist Leyla Arner started with the leafy background image at full intensity. She used a channel to select all of the background image except the word "Leaf."She floated this selection so she could use the Opacity slider in the Image Channels palette to "wash out" the image around the type.

You can try this effect with your own words and images. For the background, select an existing image, or create one using the painting tools. You can paint color swatches, blur them and use the Smudge tool to create a background of color swirls, for example.

For the type, use the Text tool to create a word or phrase. The type should be solid black because it will be used in an image channel, where selections are based on lightness values. You can use the Font and Size submenus (in the Text menu) or the Type palette to set the typeface and size. Then convert the text to paths as described above.

Type pasted into background image

Step 1: Create a channel from the type

Select your type object and copy it to the Clipboard (choose Copy in the Edit menu). Double-click your background image to go into edit mode. Choose Show Channels in the Image menu to open the Image Channels palette. The palette shows the separate color channels of the background image.

Paste the copied type into the image by choosing Paste in the Edit menu (or press Command+V on Mac, or Ctrl+V on Windows). The type appears as a selection centered in the image. If you want to move the type, press the keyboard arrow keys to nudge it into position.

To create a channel based on the type selection, click the Selection button (the dashed circle) at the bottom of the Image Channels palette. A new channel appears, with solid white type on a black background. The channel corresponds to the current selection: white areas in the channel (the type) indicate selected pixels, and black areas indicate unselected pixels.

Now you can delete the type from the image by pressing the Delete key. The shape of the type is preserved in the channel you just created, so you don't need the actual type in the image.

Step 2: Select the background around the type

Now, you can use the new channel to select everything in the background image except the type area. Drag the new channel to the Selection button (dashed circle) in the Image Channels palette. The selection appears in the image as a moving marquee (or "marching ants"), outlining the type area.

Because you want to lighten the background, and leave the type area as is, you need to invert the selection. In the Image menu, choose Select >Inverse. Now all of the image, except the type area, is selected.

Adjust the opacity of the selection

To adjust opacity so the background appears to fade to white, the selected area needs to be "floating" with a white background behind it. If you simply float the selection, the background pixels are the same as the floating selection, so adjusting the Opacity slider has no effect.

You can float the selection and fill behind it with white in one step. First, make sure that the background color shown in the toolbox (the bottom brush icon) is white. Then, press Option (Mac) or Ctrl (Windows) as you choose Select > Float in the Image menu.

Now, the Opacity slider at the bottom of the Image Channels palette is available. Drag the slider to the left, to a lower Opacity setting, to lighten the selected area. This happens because the lower Opacity lets the white show through the floating selection.

Try some other options: If you choose another background color before floating a selection with the Option or Ctrl key, the color you select will show through as you reduce the Opacity of the selection. Rather than "washing out" the selection with white, you can tint it with the current background color.