But MTF tests have two curves , tangential and sagittal and we found that two relates to astigmatism. But your latest post and I have read in books says MTF shows the combination of all aberrations.

Whats going on ? I could not get it. Is it telling the aberrations in astigmatism ? By the way , I found a reference about the authors who got their prescriptions from ELCAN archive and conduct tests on Summilux , f:1 one and Summicron 50 f:2. They analysed mandler designs and the double gauss ones.

All they found , there is virtually no aberration record at summicron , but for others all aberrations are so low but one single abnerration is 10 times more. I never heard that one in any book.

IMHO , If they would put under MTF test , they would be worse than Zeiss or Nikon. But it does not say the all story.