Render at higher resolution, apply shader, downsample

Godot Version

` 4.3 stable

Question

` I want to apply a very drastic fisheye shader to my game. My camera2D by default is zoomed out a lot to capture as much of the game level as possible. However, since the middle of the screen gets zoomed in by the shader as intended, there are not enough pixels produced by the camera in the first place to maintain the quality in the central zoomed in region of the screen.
Is there a way to render way more pixels per same area of the gamelevel, apply the shader, and then downsample the resulting image to the actual pixels available to the display?