One of the main things that Photo Booth is known for is the Photo Booth effects that it includes. To the right of the picture button will be an

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Effects button. Once you hit that you will be taken to a nine pane image of what the camera is seeing, each with a different video effect. There will be four pages of this: the first being color and image focused effects, the second being perspective effects such as stretching, the third being background effects like being amongst the clouds, and the third being background effects where you insert the background image you want. Just click into the effect pane that you want and then the camera will come up with that effect, and you can then go through the same picture capture process that was outlined before. When the picture is saved it will be saved with the Photo Booth effect that was chosen and appeared during the image preview.