Anamorphic Lenses

The simple way to setup an Anamorphic lens is to 

1. Select the camera you will be using 
2. Go into its optical properties and create a new Frame Size with the width of the film/sensor multiplied by the squeeze factor of the lens.  Thus is it is turning 4:3 into 2.39:1 you do the following:
   1. Convert any aspect ratios like 4:3 into a single number, in this case 1.3333.  
   2. Divide the effective aspect ratio gotten by the camera with this lens (in this case 2.39) by the original aspect ratio, in this case 1.333
   3. The squeeze factor would thus be 2.39 / 1.33 which comes out to 1.79699
   4. Take the camera's current film/sensor width and multiply it by that number and enter it and the final aspect ratio in the definition of the film /frame size
3. Use that newly created Film/Frame Size and you will see the final unsqueezed results at any given focal length