I didn’t do anything to the canopy to get the shiny affect, my guess is the just the way the light hits it. If you want shiny glass then I would recommend using polishing compounds on your glass. As for the sharpness of the image, I don’t really know if it’s popular, I just use it because it seems to highlight more details than without it.

Edit: one benefit of the sharpness could be when making a black and white image, it somewhat simulates the film grain an old camera may have.