I did tests on my f/1.4, but I can't upload them onto my web page because the free AT hosting is down, and Smugmug can't display rows of full sized photos side by side, and of course this forum software doesn't allow viewable pictures in threads.
At wide open I definitely have the purple halation, but it is more or less gone at f/1.6. My lens is strange though. With AF the image is crisp at apertures at and close to wide open, BUT as I stop down the images actually become LESS crisp when AF-ing at each aperture. When I manual focus using my Katz Eye and hold this focus for all my shots as I incrementally stop down the lens, the shots that are stopped down are really really crisp, but become less crisp as it gets closer to wide open.
At wide open I definitely have the purple halation, but it is more or less gone at f/1.6. My lens is strange though. With AF the image is crisp at apertures at and close to wide open, BUT as I stop down the images actually become LESS crisp when AF-ing at each aperture. When I manual focus using my Katz Eye and hold this focus for all my shots as I incrementally stop down the lens, the shots that are stopped down are really really crisp, but become less crisp as it gets closer to wide open.