Hi,
Found this explanation of "short throw" though have never seen FL taken
into account.
""> It is long compared to some (most?) other macro lenses, but
> likely somewhat shorter than non-macro lenses.
>
> I'll check this at home, and report exact numbers here.
It's a good thing I measured this, because you are right,
and I'm wrong. I overlooked that the Voigtlander focuses
down to 1:1, and the MF Micro-Nikkors just to 1:2. That makes
up for the extra full focusing turn of the Voigtlander.
To get a value that is independent from the
focal length, it is better to measure the
angle between infinity and some fixed multiple
of the focal length. 20x is a good value, for which
angles between 50° and 170° are OK, and between
70° and 120° best for most people.
Here are the angles between infinity and 20x focal
length for some lenses:
150° Pentax Super-Takumar 3.5/135
146° Leica Elmarit-R 2.8/180
120° Nikkor AI 2/85
104° Zeiss Sonnar T* 2.8/180
95° Nikkor K 1.8/85
90° Nikkor AI 3.5/135
80° Nikkor AI 1.2/50
72° Nikkor AI 2.8/180 (non-ED, ED is just slightly different)
72° Nikkor AI 2.5/105 (the AI-S has a shorter focusing throw)
60° Nikon Series E 2.8/135
40° Nikkor AI-S 2.8/28
40° Vivitar 2.8/100 Macro
34° Micro-Nikkor-P 3.5/55
32° Micro-Nikkor 4/105
27° Voigtländer 2.5/125 Macro
So the Apo-Lanthar has the shortest focus throw of the lenses
I measured. I'm sure there are still shorter throws in some
zoom and especially AF lenses, though. "
I tried to fix the columns manually a bit. I hope it is at least
legible without being headache inducing. Should be quite high contrast
with nice performance at 10 lp/mm. I would think there is not a
dramatic fall off in performance until near edge of lens at higher
resolutions.
Mike
125mm F2.5 inf F2.5
defocus -0.020
10/mm M 10/mm 20/mm 20/mm 30/mm 30/mm 40/mm 40/mm
0 0.989 0.989 0.956 0.956 0.908 0.908
0.853
3 0.989 0.989 0.956 0.957 0.908 0.911 0.852
0.858
6 0.988 0.988 0.952 0.953 0.899 0.901 0.835
0.841
9 0.984 0.986 0.939 0.945 0.870 0.885 0.785
0.812
12 0.979 0.985 0.918 0.942 0.826 0.878 0.714
0.802
15 0.973 0.982 0.900 0.933 0.793 0.861 0.669
0.779
18 0.965 0.970 0.879 0.889 0.778 0.780 0.677
0.667
21.633 0.911 0.951 0.767 0.824 0.687 0.663 0.637
0.515
F8 defocus -0.020 F8
10/mm 10/mm 20/mm 20/mm 30/mm 30/mm 40/mm 40/mm
0 0.999 0.999 0.996 0.996 0.990 0.990 0.983
0.983
3 0.999 0.999 0.996 0.995 0.992 0.988 0.985
0.979
6 0.999 0.998 0.997 0.991 0.993 0.980 0.988
0.966
9 0.999 0.996 0.996 0.985 0.992 0.967 0.986
0.943
12 0.998 0.994 0.993 0.976 0.985 0.948 0.973
0.912
15 0.997 0.991 0.989 0.965 0.976 0.924 0.958
0.872
18 0.997 0.988 0.988 0.952 0.973 0.897 0.953
0.829
21.633 0.999 0.982 0.994 0.930 0.987 0.850 0.978
0.752
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