Image Effects - Affecting Camera#ScreenPointToRay()

I have a simple game in which players have to click squares on a grid, which looks like this: http://gyazo.com/fa363afd6c6985940ec3b16e4e581e38 To calculate whether the player has clicked on a square, I'm simply using ScreenPointToRay. I discovered that if I apply a vortex image effect to the camera, I can make the grid more challenging to click: http://gyazo.com/ff5ae90d21b5763adce258215a8d1f60 I would like to find out how I can make the ray be inversely affected by this, meaning that when I click the rendered 'morphed' image, the game behaves as expected and registers the click to the object that the mouse is over.