Originally posted by StephenMerola I bet the 120mm macro is. That lens is SHARP!
You made me curious. And so I checked what the internet can tell me.
Photodo has a few Pentax 645 MTF data (no 645 AF data though) and the best MTF is from the Pentax SMC P-A 645 Macro 120mm/4.0 lens. I compared this to the corresponding Leica S2 lens which has public MTF data too.
Left column: Pentax SMC P-A 645 Macro 120mm/4.0
Right column: Leica APO Macro Summarit-S 120/2.5 (CS)
The Pentax width goes to 33mm, Leica to 27mm only. So, imagine a virtual right edge in the Pentax graph at 27mm.
The three lines for Pentax are at 10, 20, 40 lp/mm, the four lines for Leica are for 5, 10, 20, 40 lp/mm. Just compare the lowest corresponding lines (40 lp/mm).
The apertures are as follows (left -- right / top down):
Pentax f/8 -- Leica f/2.5
Pentax f/4 -- Leica f/5.6
Especially the
Leica f/5.6 40 lp/mm MTF curve
is an unbelievable MTF monster this Pentax lens cannot even come close. At f/8, the Pentax lens has just enough resolution in the very center.
I couldn't find more data and I don't know how sharp the Pentax SMC P-A 645 Macro 120mm/4.0 lens really is. From our own lens database (average rating 9.4) I read: "Sharp sharp sharp", "razor sharp optics", "Very sharp", "Extremely sharp". So, can't be that bad
This new era of digital MF will bring all of us some very outstanding glass. Seems like the new Leica S2 is more about the glass than anything else.