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increase rendering quality
I was looking for a special options on glass qualities.
Anyway, that worths to try increasing the whole quality. Thank you for your answer ali!
you may try to change the scene or play with the lights but usually such a problem needs higher quality.
I cannot tell exactly from your photo but try to reduce surface reflections
these are reflections...try changing scenes...(for eg. 3 point faded...)
as you can also see there are some reflections on these glasses...
Also here is something I posted as a stand alone but can just as easily be helpful here...it gives a direct understanding what each setting changes