Another rewording of the lens model

Author: hollasch

books/RayTracingInOneWeekend.html

@@ -2759,7 +2759,7 @@
 <div class="together">
 We don’t need to simulate any of the inside of the camera. For the purposes of rendering an image
 outside the camera, that would be unnecessary complexity. Instead, I usually start rays from the
-lens aperture, and send them toward the projection plane (`focus_dist` away), where everything on
+lens, and send them toward the focus plane (`focus_dist` away from the lens), where everything on
 that plane is in perfect focus.
 
   ![Figure [cam-film-plane]: Camera focus plane](../images/fig.cam-film-plane.jpg)