It looks like the SEL50F14Z Planar T * FE 50mm F1.4 ZA has a fogging issue that Sony is going to fix regardless of warranty status. You can see the translated release below.
Translated Release:
Thank you for your interest in Sony products for a long time.
We found that in the SEL50F14Z Planar T * FE 50mm F1.4 ZA (hereinafter referred to as “SEL50F14Z”), some of the lens lens may produce a “fog” phenomenon. In response to this phenomenon, we will provide free inspection and maintenance services (including preventive repair).
If you have one or more SEL50F14Zs within the range of the fuselage numbers listed below that meet the specific conditions of free repair, please contact your nearest Sony service station. Sony special service station information can be found through the Sony official website: http://service.sony.com.cn/Maintenance_Station/2518.htm
【Involved models and fuselage range】
model: SEL50F14Z (E-card) exchange lens
Fence number range:
1,1800001 – 1810699
2,8300001 – 8300119
【Specific behavior for free maintenance
There is a “fog” phenomenon in the lens of the lens or may be “fog”
How to confirm the fuselage number
The fuselage on the side of the camera will be marked on the fence
[Free service duration]
To October 31, 2019 only
* This announcement applies only to China (Mainland China).
If you have any questions about this, please contact the Sony China Customer Hotline.
Service Hotline: 400 810 9000
Service Hours: Monday to Saturday: 9: 00-21: 00
Sunday: 9: 00-18: 00
E-mail: [email protected] We are very sorry to bring you the inconvenience, thank you for your understanding and support as always.
Via Sony China