Popular Photography Lens Performance Comparison    
 
Lenses Tested: Mamiya-Sekor E 50mm f/1.7 from Mamiya ZE      The Mamiya-Sekor 50mm f/17 E-series lens tests favorably
  Nikkor 50mm f/1.4 from Nikon F3        against some of the best names in the business: Nikkor, Zeiss
  Planar T 50mm f/1.4 from Contax RTS II Quartz      Planar and Canon FD. Review the test results, as published
  Canon FD 50mm f/1.2 from Canon New F-1      Popular Photography, and judge for yourself.  
 
Lens:  Mamiya-Sekor E 50mm f/1.7   (tested January 1981)
 
Aberration 1/3 Out 2/3 Out Far Edge Notes LENS TEST GLOSSARY  
Coma 4.5 5.6 6.3 Critical  
Astigmatism 3.5 3.5 3.5 f-stops Coma: Comet- or teardrop-shaped images
Lat. Chrom. None Slight Moderate   of off-axis points of light. Improved by
Long. Chrom. blue--green--red = 0.08mm Focus stopping down.  
Spherical f/1.7 -- f/5.6 = -0.03mm shift  
Distortion Very slight barrel         Astigmatism: Causes lines radial to the
Vignetting None beyond f/2.8   optical axis, and lines perpendicular to
Centering Perfect   them, to focus in two different planes.
 
Lens:  Nikkor 50mm f/1.4   (tested April 1981)  
Lateral Chromatic Aberration:
Aberration 1/3 Out 2/3 Out Far Edge Notes A variation of magnification with color. Not
Coma 1.4 2.2 4.5 Critical improved by stopping down.  
Astigmatism 1.4 1.4 1.4 f-stops  
Lat. Chrom. None None None   Longitudinal Chromatic Abberation: A
Long. Chrom. blue--green--red = 0.06mm Focus shift of focus with color. Not improved by
Spherical f/1.4 -- f/4.0 = +0.02mm shift stopping down.  
Distortion Moderate barrel        
Vignetting None beyond f/2.2   Spherical Abberation: Causes a focus
Centering Perfect   shift as the lens is stopped down.
 
Lens:  Zeiss Planar T 50mm f/1.4   (tested February 1983)
Distortion: Causes image to bow out
Aberration 1/3 Out 2/3 Out Far Edge Notes (barrel) or bow in (pincushion), but does
Coma 2 4.5 5.6 Critical not influence sharpness. Not improved by
Astigmatism 1.4 1.4 1.4 f-stops stopping down.  
Lat. Chrom. None None None    
Long. Chrom. blue--green--red = 0.03mm Focus Vignetting: Causes underexposure at the
Spherical f/1.4 -- f/5.6 = +0.06mm shift film corners. Improved by stopping down.
Distortion Slight barrel        
Vignetting None beyond f/2.2   Centering: The center of curvature of
Centering Near-Perfect   each lens should lie on a common line.
 
Lens:  Canon FD 50mm f/1.2   (tested August 1982)  
Critical f-stop: The largest opening at
Aberration 1/3 Out 2/3 Out Far Edge Notes which the abberation being examined is
Coma 1.2 2.8 4.5 Critical considered under satisfactory control.
Astigmatism 3.5 5.6 1.2 f-stops    
Lat. Chrom. None V. Slight V. Slight   Close working limits are measured
Long. Chrom. blue--green--red = 0.08mm Focus from the target to the foremost portion of
Spherical f/1.2 -- f/4.0 = +0.02mm shift the lens when it is set to its closest
Distortion Moderate barrel       focusing position. Close-limit field size
Vignetting None beyond f/2.8   is measured at this point, and portions of
Centering Perfect   the field are also measured 1/3 out, 2/3 out,
  and far edge -- and correspond to 16mm,
    12mm and 18mm off-center, respectively.
©  2002   R.L Herron