When I work with 8-bit images in Photoshop I never achieve to get smooth gradients when working with dark colors. I looks bad and it's a clear line between dark gray and black. My guess is that is because I work 8-bit files but is there any reason at all to not use 32-bit images on the web? Sure, they have a greater file size but is that the only reason? It doesn't have anything to do with web browsers and incompatibility with 32-bit images?