Rangefinder Magazine
May 2006

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Photoshop CS² How² by MICHELLE PERKINS
Vanishing Point: Added Dimension in Photoshop CS

Photographs are flat; the world is not. That won’t come as a surprise to anyone who has tried to convey a sense of depth in a medium that is inherently two-dimensional.

Until now, Photoshop has been pretty much limited to two dimensions as well—like the photos it was designed to work with. With the addition of the Vanishing Point filter, however, Photoshop CS2 has delved into the third dimension, allowing photographers to make perspective-correct edits on images that contain planes (flat surfaces such as tabletops, streets, the sides of buildings, etc.).

Getting Started

To begin, select an image with readily identifiable planes—perhaps a photograph of a building. If you like, duplicate the background layer to preserve your original image. If you plan to make any edits that will extend beyond the existing edges of the frame, add some extra canvas around the image before going to the Vanishing Point filter. Should your plan for the image involve pasting an item from the Photoshop clipboard into Vanishing Point, you should also copy this item before going to the Vanishing Point filter. To confine the results to a specific area of your image, make a selection or add a mask before opening Vanishing Point.

Image 1—This image contains readily identifiable planes—flat surfaces that advance and recede at a variety of angles.

Create One or More Planes

Go to Filter > Vanishing Point. In the full-screen dialog box that appears, choose the Create Plane tool and click on the four corners of a plane surface. It’s easiest to do this when a rectangular object is available (in this case, the corners of the window).

Image 2—In the Vanishing Point dialog box, the Create Plane tool was used to define the four corners of the window on the enclosed staircase.

Once you’ve placed the four corners, you can move, scale, or reshape the plane (which looks like a grid) by using the Edit Plane tool to click and drag the nodes (the white boxes at the corners and edges). The success of your image-editing depends on this grid being accurate, so take your time. Keep an eye on the color of the grid, as well. Valid grids are blue. If your grid turns another color, it means Vanishing Point can’t calculate the plane’s aspect ratio (red) or resolve the vanishing points (yellow). As a result, any edits you make won’t be oriented properly.

Depending on the image and work you plan to do, you may need to define several planes. To keep your edits at the proper scale and orientation throughout the image, you can “tear off” new planes from the old ones. To do this, select the Create Plane tool again. Press Crtl/Cmd and drag an edge node of an existing plane to tear off a perpendicular plane. This allows you to wrap your grid around the corner of a building, for example.

Image 3—Tearing off allows you to link multiple planes (here, around the corner of the building) and ensure your edits are made at the proper scale and orientation throughout the image.

Edit Your Image

Once you have defined the planes that make up your image (at least in the areas you want to edit), you’re ready to get down to business. From within the Vanishing Point dialog box you can select a number of tools.

Selections.

Selections are made by choosing the Marquee tool and dragging within a plane. At the top of the screen you can adjust the Marquee tool options (Feather, Opacity, Heal, and Move Mode) either before or after making a selection.

To clone an area of the image, press Alt/Opt and drag an active selection. The area will become a floating selection that can be dragged anywhere in the image. Whether you move this around on its original plane or drag it to another plane, the image data will automatically conform to the de-fined plane.

Image 4—The original window was cloned as a floating selection. Moving it “back” (away from the original camera position) causes it to get smaller, receding into the frame just as the wall does (left). Moving it “forward” (toward the original camera position) causes it to get bigger, advancing into the frame just as the wall does.

Image 5—The arched window was cloned as a floating selection. When it was moved to other planes within the image, the data automatically corrected for the changed angle of view and distance to the camera. The Heal option was on for both of the moves shown here. This helped blend the results—it’s not perfect, but it’s a good start and wouldn’t be hard to fix after leaving Vanishing Point.

To fill a selection with another area of the image, press Ctrl/Cmd and drag an active selection to the area you want as the source image (i.e. the area you want to use to replace the selected area). This is a great way to cover problem areas on angled walls where the texture or pattern would make using the Clone Stamp tool impossibly laborious. In this example, imagine the work that would be involved in removing this window with the Clone Stamp. With the Vanishing Point filter, it took about 30 seconds!

Image 6—Here, the window at the top left was quickly removed by filling the area with the bricks to the right of the window. Because the plane of the wall was defined, the bricks automatically lined up perfectly. With the Heal setting active, the blending looks very good.

Painting and Cloning.

To paint with a sample of the image, choose the Stamp tool. Then press Alt/Opt and click in a plane to sample an area. When you paint on that or any other plane with the Stamp tool, the cloned image data will automatically conform to the plane’s perspective. Similarly, you can paint with a color by selecting the Brush tool. When painting on a plane, the brush tip and shape will orient to the perspective of the plane.

Image 7—In Photoshop’s normal editing area, the Brush tool is applied as if to a two-dimensional surface. The line of paint is the same from start to finish.

Image 8—When applied to a defined plane in Vanishing Point, the size and shape of the brush tip match the plane. Here, the line of paint grows narrower as it moves away from the camera position and the brush grows more angled.

Pasting.

With an item already copied to the clipboard, go to Filter > Vanishing Point and press Ctrl/Cmd + V to paste the item. After pasting the item, move the item onto a plane and watch it conform to the perspective. (Note: After pasting into Vanishing Point, do not immediately use the Marquee tool to select a plane. This deselects the image so it is no longer a floating selection.) To scale or rotate the pasted item, use the Transform tool to move the bounding box handles. If you want the flexibility of having your pasted data appear on a separate layer when you exit Vanishing Point, create a new layer before going to Vanishing Point and make sure this layer is active when you start the filter.

Image 9—Only raster (not vector) items can be pasted. If you want to paste text, select the entire text layer and copy it to the clipboard. When you paste it, the text will appear as a rasterized version in Vanishing Point. Moving it from plane to plane will change its size, orientation, and perspective.

Additional Tips

• To preserve the perspective planes you’ve created in your image, simply save the document as a PSD, TIFF, or JPEG.

• Vanishing Point supports multiple undos (Ctrl/Cmd + Z) and redos (Shift + Ctrl/Cmd + Z).

• Pressing Alt/Opt turns the Cancel button into a Reset button, taking the image back to its original state in the Vanishing Point dialog box.

In Closing

For photos that include definable planes—whether these are the subject of the image or simply an element of the background—Vanishing Point is a handy tool. While the edits it enables weren’t impossible without it, many will be much easier to tackle with the automation it provides. Vanishing Point also takes the guesswork out of some of these tasks, ensuring that you maintain the proper size and perspective when moving elements about on angled surfaces.

11 - Vanishing Point key commands.