To crop a canvas

1. Select the area to be cropped or extended with Paint > Select > Marquee (rectangle) , Paint > Select > Marquee (ellipse) , Paint > Select > Marquee (lasso) , or Paint > Select > Marquee (polyline) .
2. Select Canvas > Crop to marquee.
   • If the selected area is smaller than the image plane, the image plane will be cropped. If the selected area is larger than the image plane, the image plane will be extended.
   • If you select the area using either the lasso, polyline, or ellipse marquee, the image plane will be cropped or extended to the edges of a bounding box encompassing the marquee.