Roger Cicala from Lens Rentals always writes with clarity about technical issues. If you’ve ever wondered about MTF charts this should help a lot.
Two takeaways for me and one note:
- Lens Acutance can be improved with sharpening in post, lens resolution can’t.
- Differences in the MTF between sagatial and meridal result in differences in the bokeh or out of focus areas of a lens. The closer the two lines are, the better the bokeh (perhaps a bit subjective).
And the note – Roger writes as if most lens makers publish MTF that are measured, but in fact most are not measured from production lenses, but instead calculated from the optical design.
Have you seen my acutance? A few words about sharpness and MTF charts Many of you know one of my pet peeves is strident internet arguments between photographers who are splitting hairs or misinformed. One major cause of these arguments is terminology: people use a nonspecific term which means something different to each of them. […]
Source: Have You Seen My Acutance?