2 Shots with Samyang 85/1.4

I was encouraged by seeing Prostotak's shots, and got this lens.

There was a car show last month in our city, and I tried to use the new lens, Samyang 85/1.4. It was extremely tricky for me to focus right on the models' eyes, more than 50% were out of focus due to my poor eyes. However, I was impressed by its sharpness and color. Samyang could be quite a choice if your eyesight is good enough. Anyone's comment on better use of this lens will be highly appreciated.
K5 & Samyang 85/1.4

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Best regards,
Yang