I’m using my iPad Pro 2018 version as a backlight with a Fuji xt3 and 80mm macro to digitize my negatives. I’ve just started and am trying to find my rhythm. At the moment I have a piece of anti reflective glass (it’s slightly textured) raised a few cm. above the iPad screen with a couple piece lens of regular glass on top and a negative film holder. The reason for all the glass is to raise the negatives away from the screen to avoid pixels. Is this regular film grain (Portra 400 35mm) or does this look like some distortion from the glass or possibly iPad pixels showing through?
To my eyes, that does not look like regular film grain… I think the texture you are seeing is either from the iPad pixels, or the texture from the glass.