8.5 Rendering Project I: Drop Shadow and Punchout
To illustrate some of the techniques discussed in this chapter, let's
apply them to a project using the image shown in
Original Image and Color Corrected Selection of Astronaut
The astronaut in this image is selected from its background using
various methods from Chapters
After the selection, methods described in Section
are used to improve the tonal range, and the result is shown in
This project uses a drop shadow and a punchout to create a composition
with our astronaut. The goal is to create the effect that he has
extracted himself from the 2D plane and is wandering off on his own.
To start, the selected astronaut is placed over a blue-gray layer. The
result of this is shown in Figure
Making a Gray-Blue Background Layer and Creating a Channel
Mask from the Astronaut's Alpha Channel
and the associated Layers dialog is shown in
The most important element of the project is the outline of the
astronaut because this is used to create both the shadow and the
punchout effects. Thus, the next step is to save the outline as a
channel mask. This is done by making the Astronaut layer active,
applying the Alpha to Selection function found in the Layers menu, and then using Save
to Channel from the Image:Select menu. This creates the channel mask shown in
8.24(c). After the save-to-channel
operation, it is important to cancel the selection by typing C-S-a in the image window.
The punchout is made first. This is begun by copying the astronaut
mask and pasting it into a new layer. This new layer, labeled Punchout,
is positioned between the Blue Gray Background layer and the Astronaut
layer as shown in Figure
Starting the Punchout
To create the punchout, this new layer is copied into its own layer mask
as shown in Figure
All that remains to finish the punchout effect is to blur the image in
the Punchout layer and to offset it.
Finishing the Punchout
shows that a value of 20 is chosen in the Gaussian Blur (IIR)
dialog, and Figure
(b) shows that values
of 8 and 4 have been chosen in the Offset
dialog. The result is shown in
(c). Note that, for the punchout
to be seen in Figure
(c), the visibility
of the Astronaut layer has been toggled off, as shown in
Before moving to the next stage of the project, let's give the
punchout a bit more pizzazz by inserting an interesting image pattern.
To do this, the Punchout layer is duplicated by first clicking on its
thumbnail in the Layers dialog, and then clicking on the Duplicate
Layer button. This creates a layer called Punchout Copy just above
the original. The image part of the Punchout layer is made active by
clicking on its thumbnail. This layer is now filled with the pink
marble pattern from the Pattern Selection dialog (see
8.27(c)). This is done using the Bucket Fill tool, where the fill type is set to Pattern Fill and the
Threshold is set to 255. Finally, the Mode menu for the Punchout Copy
layer is set to Multiply, as shown in
Jazzing up the Punchout with a Pattern Image Background
This produces the result shown in
(a), which makes it appear as if
the wall behind the Background layer is made of pink marble.
The final step of this project is to rotate the astronaut, reposition
him, and give him a drop shadow. To do this, he is first made visible
by clicking on the Eye icon of the Astronaut layer in the Layers
dialog. The rest is detailed in the following steps:
- Rotate the astronaut using the Transform tool.
- Move the astronaut to a new position using the Move tool.
- Duplicate the Astronaut layer, creating a layer labeled Astronaut
- Set the threshold of the Bucket Fill tool to 255 and use it to
fill the Astronaut layer with black.
- Blur the Astronaut layer with Gaussian Blur (IIR).
- Offset the Astronaut layer an appropriate amount.
The final result is shown in
The Final Rendered Image
The resulting Layers dialog is shown in