Begin by pressing and holding the lens-release button with your right hand (or have a helper do this).

Grasp the outside barrel of the lens with one or two hands, and start to rotate it counter-clockwise. Be prepared to support the weight of the lens as it is released from the locking mount.

It will rotate about 45 degrees -- watch the mark on top of the pictured lens for the start and end points.

After rotation stops, slide the lens out of the projector.