Note: Steps and examples make reference to Photoshop 5.0/5.5 commands.
What are clipping paths?
Clipping paths are sharp, hard-edged shapes that are used to cut around objects in an image, allowing the background layer to show through. The very 'hard-edged' nature of these paths makes them inappropriate for transparent objects or for very fine details, but for many graphic applications, clipping paths are a necessity. Even though Maskerade generates transparency and not clipping paths, you can easily generate a clipping path in Photoshop from the transparency in a Maskerade image under certain circumstances.
Objects appropriate for clipping paths
- Non-reflective, opaque foreground objects.
Objects not appropriate for clipping paths
- Highly-reflective foreground objects. It is possible to generate clipping paths for these types of objects, but the placement of the background is critical. If the background is moved far away from the object so that it does not appear in the reflections in the object, you will be able to generate a useful clipping path. If the background is underneath or very close to the objects, it will reflect in the object and Maskerade will treat these reflections as transparency.
- Transparent objects. Transparency cannot be reproduced with a simple clipping path. In this case, you should composite the transparent image on the final background, then build a clipping path around the object by hand.
Generating clipping paths
There are several techniques for generating a clipping path from a transparent image in Photoshop.
Method #1 (fast & easy)
- Select the "Maskerade Image" layer in the "Layers" palette.
- Choose "Load Selection " from the "Select" menu.
- Choose the "Maskerade Image Transparency" channel from the pop-up menu, and select "New Selection" as the operation. Choose "OK".
- Select "Show Paths" from the "Window" menu.
- Choose "Make Work Path " from the pop-out menu in the "Paths" palette.
- Enter a tolerance of 1.0 to 2.0 pixels, depending on the complexity of your foreground object(s).
- Double-click the "Work Path" path in the "Paths" palette and rename it appropriately.
- Flatten the image onto a solid-colored background layer.
- Save the file as an EPS with the path selected as the clipping path.
Method #2 (slower with more control)
- Select the "Maskerade Image" layer in the "Layers" palette.
- Choose "Load Selection " from the "Select" menu.
- Choose the "Maskerade Image Transparency" channel from the pop-up menu, and select "New Selection" as the operation. Choose "OK".
- Choose "Save Selection " from the "Select" menu.
- Choose the "new" channel from the pop-up menu, and select "New Channel" as the operation. Choose "OK".
- Choose "Deselect" from the "Select" menu.
- Select "Show Channels" from the "Window" menu.
- At this point, you have extracted the layer's transparency into a visible channel which you can see and manipulate. By adjusting the grayscale values of the channel, you can control how Photoshop will trace the channel with the "Load Selection " command, which will control the location of the paths made from the selection.
- When you use the "Load Selection " command, Photoshop traces along the 50% gray values in the grayscale channel to make the selection. By adjusting the grayscale values of the channel using the "Levels " or "Curves " command under the "Adjust" submenu of the "Image" menu, you can shift the 50% gray values inward or outward, relative to the objects in your image. The next time you use the "Load Selection " command, Photoshop will make a different selection by tracing the shifted 50% gray values.
- After adjusting the channel, you would generate a clipping path using the same steps as in method #1, but you would select the new channel in the "Load Selection " dialog instead of the "Maskerade Image Transparency" channel as you did in method #1.
Touching up a Maskerade image in Photoshop is easy, but you need to be familiar with editing transparent layers to get the results you really want.
When you open a Maskerade image in Photoshop, you will have one or two layers, depending upon how the preferences were set in Maskerade when the image was saved. In order to identify areas that should be completely transparent but aren't, you will need to hide the background layer (if one exists) and use the "Opacity" readout in the "Info" palette to identify the not completely-transparent pixels.
- Select "Show Layers" from the "Window" menu.
- If a background layer exists, there will be a layer named "Background". Click the small eye icon on the left to hide the "Background" layer.
- You should see a checkerboard pattern through the "Maskerade Image" layer. If you like, you can change this pattern using the "Transparency & Gamut " under the "Preferences" submenu of the "File" menu.
- Select the "Maskerade Image" layer in the "Layers" palette.
- Choose the "Show Info" command in the "Window" menu.
- Click on the small eyedropper icon on the left of the palette and choose "RGB Color" from the pop-up menu.
- Click on the small eyedropper icon on the right of the palette and choose "Opacity" from the pop-up menu.
- Move the cursor around the image, and observe the opacity value.
- Use the eraser tool with the "Paintbrush", "Pencil" or "Block" option in the "Eraser Options" palette to erase the offending pixels in the "Maskerade Image" layer.
Pixels that are completely transparent should have an opacity of 0%. Pixels that are opaque should have an opacity of 100%, or an opacity appropriate for that part of the object(s).You can also identify areas to be cleaned up by observing the RGB color values when a background layer is present and visible. It is usually easiest to use a solid white background since any noise in the periphery of the image will be most noticable on it, however, you can use a layer of the same color as your final layout instead.
- Select "Show Layers" from the "Window" menu.
- If a background layer exists, there will be a layer named "Background". If the layer is not visible click the left-most well to show the "Background" layer. A small eye icon will appear in the well when the layer is visible.
If no background layer exists, you will need to add a new layer.
- Select "New Layer " from the pop-out menu in the "Layers" palette, name the layer appropriately, then choose "OK".
- Drag the layer from above the "Maskerade Image" layer to below it.
- Choose the appropriate foreground color using the color picker.
- Choose the "Fill " command under the "Edit" menu.
- Select the contents to "Foreground Color, set the opacity to 100%, select "Normal" mode and turn off "Preserve Transparency". Choose "OK".
- Select the "Maskerade Image" layer in the "Layers" palette.
- Choose the "Show Info" command in the "Window" menu.
- Click on the small eyedropper icon on the left of the palette and choose "RGB Color" from the pop-up menu.
- Move the cursor around the image, and observe the RGB color values.
- Use the eraser tool with the "Paintbrush", "Pencil" or "Block" option in the "Eraser Options" palette to erase the offending pixels in the "Maskerade Image" layer.
Pixels that are completely transparent should have RGB color values that are the same as the solid background color.The 'Transparency' channel for a layer is normally hidden from the user and can't be directly accessed. This hidden channel is different than the 'Layer Mask' or a channel that appears in the 'Channels' palette. If you have a normal, transparent layer (a layer with a name other than 'Background' in italics) and you use the eraser to erase pixels, you are changing the transparency channel for the layer.
Tip:
You can see this channel by temporarily using the preview capability of the 'Apply Image' command. Choose 'Apply Image' and, if you have numerous files open, make sure that your current document is selected in the 'Source' pop-up menu. Select the transparent layer of your file from the 'Layer' pop-up menu. In the 'Channel' pop-up menu, select the 'Transparency' channel. Set the blending mode to 'Normal' and make sure that 'Preview' is checked. You should see the grayscale data from the 'Transparency' channel previewed in the document window.
Maskerade 1.x only supports RGB for a number of reasons. First and most important is that the primary market for Maskerade is for use with digital cameras, and the native color space of these cameras is RGB. By using the native camera color space, we avoid any color shifts and conversions that can reduce the fidelity of the image and we retain the full gamut of the color space as far along in the graphic process as possible. After editing with a package such as Photoshop, the user can then determine which file format and color space the image should be reduced to for output. Photoshop provides excellent tools for color conversion, provided that the separation set-up and ink colors and/or ColorSync is properly configured.
As we expand the feature set of Maskerade, we will expand it's capabilities with support for ColorSync. But for now, we do not want to include a half-baked implementation which causes more problems than it's worth. Since the vast majority of the users will be using a companion tool such as Photoshop, the proper tools for the job will already be available in the companion tool.
Maskerade saves Photoshop files as multi-layer files with transparency so that they can be easily repurposed without having to re-mask the original photographs. Keeping a master, multi-layer file allows the user to open the file at any time, change the color or style of the background layer, then export a new copy of the file with the changed background. Since the master file is never flattened, it maintains the image transparency allowing easy repurposing.