The Sigma teased 50mm lens could be finally announced at Photokina. Months ago SAR reportsed the likely specs of this lens:
“Sigma 50/1.4 APS-C E-mount: 9 blades, less than 300g, around $600. Most probably around NAB 2018.”
This lens will be released for different mounts like Sony E, Fuji X and Micro Four Thirds.