[Leica] 28 vignette

[henningw at archiphoto.com (Henning Wulff)]

>Sounds right, Frank. The ultimate test of course is that we need 
>some folks to post some pics from other lenses. I just went back
>and found a good example from similar circumstances to my previous 
>posts. However more even lighting and I think more correct
>exposure, The others I posted were very saturated and probably 1 
>stop or so under to that end. I can detect NO fall off in ANY
>corner.
>I'm not sure if I'm beating a dead horse here or if it is still of 
>interest to some. I'll post again if anyone comes up with some
>other pics.
>
>Cheers
>Hoppy
>
>-----Original Message-----
>From: lug-bounces+hoppyman=bigpond.net.au@leica-users.org 
>[mailto:lug-bounces+hoppyman=bigpond.net.au@leica-users.org] On 
>Behalf Of
>Frank Filippone
>Sent: Wednesday, 17 January 2007 15:31
>To: 'Leica Users Group'
>Subject: RE: [Leica] 28 vignette
>
>OK.. I took a look....  The Zeiss Biogon 28/2.8 vs the Leica ASPH 
>Elmarit 28/2.8.
>
>By looking at the charts of MTF at full open ( F2.8):   It looks 
>like the Leica lens is far superior.... less fall off.
>At F5.6 .......same conclusion....
>
>
>I do not read these charts well, so I could be wrong, but it appears 
>the Leica lens is a better performer for light falloff in the
>corners......
>
>I also looked at the F2 ASPH Summicron......The Leica lens still 
>looks better......
>
>So, if one were interested in vignetting being minimized, Either 
>Leica lens would outperform the Zeiss Biogon.
>
>Frank Filippone
>red735i@earthlink.net

Hi Frank,

I used a 28 Biogon for a bit, but didn't like it enough to consider 
it. Not bad, but no reason to get one when used recent Leica lenses 
are available. I don't want to try to emulate Jeffery and corner the 
collectors' market on one focal length. :-)

 From the published charts the falloff wide open seems to be very 
slightly worse with the Biogon, but essentially equal to that of all 
the Leica lenses except for the Tri-Elmar at 5.6.

MTF curves would seem to indicate definitely better performance for 
the Leica lenses, which agrees with my findings. Unfortunately, 
comparing MTF curves from one manufacturer to another is not likely 
to mean that much unless the differences are significant, as test 
methodology plays a large part in the results.

Going by the MTF curves the overall 'best' lens is still the 
Summicron. By a slight margin, and depending on your definition of 
'best'. :-)

-- 
    *            Henning J. Wulff
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