I have created a simple grass scene with materials created in cycles.
I would like to render this image with an alpha mask and without any lighting. How would I do it?
Set the camera to Orthographic view.
Then render it as a PNG with RGBA.
Under the Film tab check the check mark for transparent.
Now if you need separate black and white image for the alpha mask.
Go to the compositer. Plug the Alpha from the render layer in to the Image socket of the Composite node.