Double Your Pleasure
The "marble and matches" image introduces a new interaction of light and shadowtwo light sources (Figure 4.38). This is evident by the shadow of the match that is leaning against the matchbox.
Figure 4.38. The "marble and matches" image introduces a new interaction of light and shadowtwo light sources.
The first light source shines from above, just slightly to the rear of the objects. It is the stronger of the two light sources. The second light is coming from the front and to the left of the set of objects. This one casts a softer, lighter shadow. The two shadows actually intersect at the lower-front edge of the matchbox. The area where they intersect is darker.
The shadow of the matchstick that is leaning against the matchbox goes through an additional transformation. Because it leans away from the surface, the shadow is softer as it moves further away from the matchstick (Figure 4.39). This is the same behavior that you saw in the shadow of the tree in the beginning of this chapter.
Figure 4.39. The shadow of the matchstick that is leaning against the matchbox requires additional work. Because of the lean in it's position, the shadow gets softer as it moves further away from the matchstick.
The area where the shadow falls was selected (Figure 4.40). I saved the selection to an alpha channel, as shown in Figure 4.41. In this new channel, I filled the selected area with a gradient that is white to give it a stronger effect at the points that are further away from the match (Figure 4.42). Then, I deselected the area, returned to the color document, and loaded the alpha channel as a selection. I then applied a blur that, thanks to the selection, diverted focus from the shadow as it moved away from the match.
Figure 4.40. The area where the shadow falls is selected.
Figure 4.41. The selection is then saved to an alpha channel.
Figure 4.42. In the alpha channel, a gradient is laid down to give the strongest effect at the point in the shadow that is furthest away from the light source.