This is an important point. I think the numbers are for lines per millimeter (lpm) not line pairs(lppm). This fits to resolution numbers for lenses that I know and to that what I can see in some of my negatives. Else my best lens resultion test negatives would only be half as good as they theoretically should be. But as I´m not totally sure, I like to ask the experts and maybe they who have read some of the recommended literature, which is right.
Well no.
The figures are decidedly too low for lines per mm.
Lens resolutions for half way decent lenses are also way up, in the region of 100 to 200 line pairs (!) per mm.
Zeiss' ZF f/1.4 50 mm resolves 320 line pairs per mm. And Zeiss' Biogon f/2.8 25 mm ZM lens actually allowed counting up to 400 line pairs per mm (recorded on SPUR Orthopan UR film). That's 800 lines per mm.
But that's a particular good lens.
Just to add: If I look at the MTF chart in this tech. pub. for TMAX 400:
http://www.kodak.com/global/en/professional/support/techPubs/f4043/f4043.pdf
Regarding that I would also speak for
lines per millimeter since at
80 cycles per millimeter which for me are analog
80 lines per millimeter
Well there you go. A cycle is pair of two lines.
So 80 cycles is 80 line pairs, not 80 lines.
Don't get hung up on MTF performance. A lens will resolve, say 160 lp/mm, even if the contrast at that frequency is reduced to 5%.
Only at 0% MTF performance can it be said that a lens doesn't resolve the particular spatial frequency, at which the contrast drops to 0.
Film's capabilities are rather better than what you think also.
As mentioned above, SPUR's orthopan was able to reproduce an impressive amount of detail. But that was shooting test targets.
In real life scenarios, a 'normal' film like T-Max will record up to 180 line pairs per mm. Portra about 140 - 160 line pairs per mm. Ektachrome 100 VS did manage 130 line airs per mm.
And if we are to believe the source of these figures (Zeiss again), that was not measured shooting high contrast targets.
Sorry to burst your bubble, but this is not correct. Both terms 'lines per mm' (l/mm) and line pairs per mm' (lp/mm) mean exactly the same. You can either count the white lines of a target, the black lines, or the number of pairs but not black and white lines together. [...]
I'm sorry Ralph, but you can.
Line
pairs per mm are definitely
not the same as lines per mm.
You can count lines, as a measure for the smallest detail an optical system can render.
You can count black and white line pairs, i.e. two lines (what else would "pair" mean?), to help you determine how good that optical system can render that fine detail.
You're only counting the white lines, skipping the black spaces separating them, however is the same as counting both "black
and white lines together". You just forget to mention that there are black lines between the white ones.
The result is the count of line pairs per mm.