Graphic Design Articles - Using Clipping Paths In Photoshop®

Using Clipping Paths In Photoshop®

A clipping path is a vector path which allows part of an image to show while hiding the rest (usually its background) effectively rendering part of the image transparent. A clipping path in an image editing program is functionally equivalent to a mask in an illustration program (more).

A clipping path is a means to make parts of an image opaque and parts of an image transparent. Usually it is used to "knock out" the background. It is also a way of changing the rectangular-shaped boundary of a bitmap image into a shape of your choice. Clipping paths are made with the pen tool in Photoshop. The path itself is a vector object, while the image is a bitmap. Together, the vector path and the bitmap image can be exported as an EPS file - a file format which is capable of having both vector and bitmap data in the same image.

The resulting EPS file can be placed directly into a page layout document such as one created in QuarkXPress™ or Adobe® PageMaker®. It can also be embedded (or linked) in a vector drawing file such as one created with Adobe Illustrator®, Macromedia® FreeHand® or CorelDRAW®. The EPS file can also be distilled into a PDF file (Adobe Acrobat® Portable Document Format) with Adobe Acrobat Distiller™. In all these applications the clipping path will knock out the background of the image.

1. Let's make one. Below is a bird over a green background. Let's cut out the bird. Then we can give the bird a new background or simply place it over a plain white background. This image was chosen because the subject (the bird) is very smooth and curved making it an ideal candidate for the pen rather than the selection tools.

2. First we use the pen to draw the path. Click the Paths tab on the Layers Palette. Then click the "New Path" icon on the bottom. The default path name for the new path is "Path 1".

3. Draw the path with the pen. Try to place as few points as possible, adding points only when necessary.

4. Below is a view of the path itself.

5. Photoshop allows more than one path to be embedded in a file. There can be only one clipping path so you have to assign which path is to be the clipping path. In the path options menu, click "Clipping Path".

6. In the dialog choose "Path 1" to be the clipping path. The flatness value determines how closely the path conforms to the curves. The lower the number, the more closely the path will conform to the curves. Enter a value and click "OK"

7. Next you need to save the file, then save a copy as an EPS file. Click:

File > Save

followed by...

File > Save a Copy

Choose "Photoshop EPS" as the file type, then enter a filename and click "Save".

8. Shown below is the effect of the clipping path. The EPS file will print out like this on a PostScript® printer. To see the effect of the clipping path on screen you can open the EPS file in a drawing program (such as Adobe Illustrator, CorelDRAW or Macromedia FreeHand) or you can place the EPS file in a page layout program such as QuarkXPress or Adobe PageMaker or you can distill the EPS file with Adobe Acrobat Distiller and view the resulting PDF file in Acrobat.

Note: If you open the EPS file in Photoshop, you won't be able to see the effect of the clipping path. To do so you either have to print it out on a PostScript® printer or view it on screen using one of the methods described above.

9. For example, you can load an image into one of the page layout or illustration programs mentioned above to function as a new background...

10. Then you can drop the EPS image right over it.

 

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