Reference Material

Color Range
One option is to use the Color Range effect. This is found in the effects pull-down under keying. It is important to note, that a well-prepared image will help in the long run. For example using a blue/green screen or any solid color for the image background. Now you can use the Color Range tool to select portions of your background and eliminate it. In the Color Range window you will have the option of using 3 different eyedroppers. Use the first to select a middle range color. Then increase the fuzziness a bit, to increase the selection. Next you will use the eyedropper with a plus sign to add more color expansion. If you add too much, you can then use the eyedropper with the minus sign. You may have to scrub the timeline to find if you need to remove any additional background color.

reference materialCreating Masks and Using Color Keys to remove backgrounds by Justin Gault

If you are fortunate enough to have a solid or nearly solid background color, you can use either the Color Range effect, or you may wish to use the Color Key effect. Each of these functions in slightly different manners, you will have to try for yourself to see which works best for your needs. If your video or image has a confusing background, say like a city street scene, you will probably want to use the Mask Tool. This will allow you to actually draw a bounding area which will designate the area you wish to remove. The Mask Tool information is towards the end of this tutorial.

Color Range One option is to use the Color Range effect. This is found in the effects pull-down under keying. It is important to note, that a well-prepared image will help in the long run. For example using a blue/green screen or any solid color for the image background. Now you can use the Color Range tool to select portions of your background and eliminate it. In the Color Range window you will have the option of using 3 different eyedroppers. Use the first to select a middle range color. Then increase the fuzziness a bit, to increase the selection. Next you will use the eyedropper with a plus sign to add more color expansion. If you add too much, you can then use the eyedropper with the minus sign. You may have to scrub the timeline to find if you need to remove any additional background color.

Color Key There are advantages and disadvantages to using the Color Key option. The advantage is when using Color Key is that you can feather the edges, allowing for a softer removal of the background. The disadvantage is that you may have to use multiple Color Keys if you background color varies in hue very much. To use, simple access through effects panel under keying. Then use the eyedropper to select the color in your background. Then vary the tolerance to broaden the color range. Again, you may have to scrub the timeline to find if you need to remove any additional background color.

Spill Suppressor Occasionally you may have to use the Spill Suppressor, in the event that some of the background color has leaked to your foreground image. Select the Spill Suppressor from the key option in the effect panel. Then use the eyedropper to select the color which is leaking to the foreground. This will remove the color.

Matte Tools For the really stubborn image you can use the Matte Tools in the effects panel. The two tools are the Matte and Simple Choker. These both use some sort of alogarithm to soften and refine the edges of the image. These tools sometimes distort the edges of your images more than is acceptable.

Masks Using masks is useful when you don’t have a solid background color to work with. Simply select the layer you want to draw the mask on. Hit “I” on your keyboard to go to the start of the clip. You then use the Pen Tool from your tools panel and draw around the image which needs to be removed from the background. This tool works much the same way that is does in Illustrator or Photoshop. Make sure to include plenty of points, in case your image will require more, later in the timeline. Once you have the outline drawn, activate the timer icon in front of the Mask Shape in the timeline. I recommend then hitting the “O” key and moving to the end of the clip. Once you are here, use the pointer tool to readjust your mask shape. Now, begin to subdivide the clip starting in the middle then halfway between points until your mask follows you image across the timeline. Under Mask in the timeline there are several useful tools. For example, you can use the feather option to soften edges. You can also use the opacity tool to fade your image in and out.



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