Above Left to Right: Canon EF 40/2.8 STM, Pentax FA645 45/2.8, Pentax FA 43/1.9 Limited; Tested on a Canon 5D3 135 Full Frame Body. (Remark: Both Pentax lenses of mine were made in Japan.)
http://smg.photobucket.com/user/RiceHigh/library/5Ds/40mm_Shootout?sort=4&page=1
Apertures from f/2.8 to f/11 were tested per lens, at nearly the same time and for the same infinity scene. Of course the image settings in the camera were kept the same.
Original full-size pictures are available for download in each individual picture page. So, go measurebate yourself for all the differences! Feedbacks are welcome for your findings, if any! :-D