Mamiya Lens Test
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New York, January, 2011 Lens Comparison Test - Update Hasselblad vs. Mamiya Intro: I wanted to compare Mamiya's new LS lenses versus Hasselblad's HC lenses, but I wanted to test only the lens quality without any influence from firmware, software or camera/computer hardware. To achieve this, I used a Pearl Resolution Power Test Projector, which allows us to test for resolution, contrast, spherical aberration, astigmatic aberration, distortion and color aberration. With the Pearl Projector there are no variable external factors like camera sharpening, proprietary software, video cards, etc, to interfere with the results. This system simply consists of light from a projector, through a chart (details below), through the lens and projected against a wall. Testing Procedures: I randomly selected four Hasselblad lenses from a well-known rental house in New York. Hasselblad 50 mm f/3.5 HC Hasselblad 80 mm f/2.8 HC Hasselblad 100 mm f/2.2 HC Hasselblad 150 mm f/3.2 HC I randomly picked the four equivalent Mamiya lenses from their warehouse's shelves in Elmsford, NY. Mamiya Sekor AF 55 mm f/2.8 LS D Mamiya Sekor AF 80 mm f/2.8 LS D Mamiya Sekor AF 110 mm f/2.8 LS D Mamiya Sekor AF 150 mm F2.8 IF D To make it even more interesting, I added two Mamiya RZ lenses to the mix, bringing the total of lenses tested to ten. Mamiya RZ 110 mm f/2.8 W Mamiya RZ 150 mm f/3.5 W
All the specs for the chart below were pulled from the manufacturers' websites.
The lenses were mounted to the projector at full-open aperture to look for corner falloff, color fringing, and resolution issues. All lenses were focused at infinity. The distance from the projector to the wall varied depending on the focal length, but was exactly the same for Hasselblad or Mamiya within the same focal range.
The chart used for this test was the "USAF Resolving Power Test Target." The chart is inside the projector so there is no way to move its position or distance from the bulb. One less thing to worry about. I replicated the projected Chart and measured the center and specific points on the horizontal and on the vertical axis for each lens. This is the chart used:
Data analysis: One person took the chart measurements and a second person did the number crunching not knowing the technical specifications for the lenses (the information was simply labeled "lens 1", "lens 2", etc). Each horizontal and vertical square (points 25 to 16 on "sample chart" above) was rated depending on image quality, determined by Resolution (how efficiently the lens transmits both resolution and contrast), and Light Falloff/Vignetting (the light variation from the center to the edges of the frame). I assigned a "grade" from 1 to 5 for each point on the vertical and horizontal axis. 5 Excellent 4 Very Good 3 Good 2 Poor 1 Very Poor We then charted a diagonal correlation between the 9 horizontal and 9 vertical measurements, and built a "test results" graph and a "performance" graph per focal length. To achieve a 100
"perfect/max" reading we took the average of the 9 points on the Test Results Chart and multiplied by 10.The best possible performance rating for a "perfect" lens would be 100 (having "5" or "Excellent" on every single point of the vertical and horizontal axis) and the worst possible performance would be 20 (having "1" or "Very Poor" on every single point of the vertical and horizontal axis).
The measured points on the horizontal and vertical axis looked like this:
And here is a closer look at each measured point:
The results: Having all the data and charts for all the lenses, I built the "overall performance" graph in order of lens tested. The best possible performance rating for a "perfect" lens would be 100 and the worst possible performance would be 20.
Higher is better
This chart shows the "final ranking" in order of quality.
Higher is better
As you can see in both graphs the best lens of the test was Mamiya Sekor AF 80 mm f/2.8 LS D. The Bronze Medal goes for the Mamiya RZ 150 mm f/3.5 W, followed by Mamiya Sekor AF 150 mm F2.8 IF D and the Hasselblad 150 mm f/3.2 HC. Eduardo Angel. [email protected]