Keep in mind that the sky at f/1.4 meters at between 1/8,000s and 1/10,000s somewhere. EXIF: \"Image Digitized: 2011:01:02, 13:41:38\" which is the brightest time of this white-sky-day. None of those three images (shot RAW) have any sharpening at all and all ACR values except color noise were set to zero (0) - the images were saved directly from ACR without passing through any other apps.
Also I think that if this lens suffered from purple fringing it would show up in images like these:
