Please help me understand. Adding a mask to an effect on an adjustment layer creates a mask that only affects the pixels in the bottom right one quarter of the frame.
I can create a mask on the opacity of this adjustment layer and that mask affects all pixels in the whole frame. That's what I want the masks on individual effects to do as well.
Of course there are properties of the mask which I can modify. Doing so changes the mask as I would expect but the mask only ever applies itself to the bottom right one quarter of frame. As if the mask itself had a layer mask.
The screenshot shows a yellow ellipse defining the intended boundary of the mask. Note the frame is only partially affected by this mask.