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

Apologies for the very dark picture!

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.

Be careful again that the back end doesn't drop as it slides out! The lenses are made of many heavy pieces of glass -- the weight can be surprising.