In case you haven’t figured it out yet, part of the purpose of this blog is to offer less expensive options in the m43 world. OM System’s newest lens is a worthy addition but still costs at least $800 USD new. I suggest you try the Leica D Summilux 25 mm f/1.4 made by Panasonic for the 43rds world, introduced in 2009. There are now many used copies available for less than half the price of the OM System Zuiko Digital 20mm f/1.4 PRO.
The Leica is wider (likely because it has a stepper motor instead of an ultrasonic one) and heavier but exudes that Leica quality with an aperture ring and a distance readout window. Both lenses are Made in Japan but the Zuiko benefits from 10 years of progress and an additional aspheric element to make a lighter and smaller optical package.The MTF graphs of both lenses are very similar, Leica on the top row at f/1.4 and f/4. Zuiko on the lower row. The large peripheral falloff in sharpness is inaccurate. Instead of using my printed ISO11223 chart which is only A3 sheet sized, I projected a chart from a 35mm lithographically etched slide. The projected chart is very large, about 130 x 70 cm and is more accurate when testing shorter focal length lenses. However my slide projector cannot project sharp corners and sharp centers at the same time so the MTF curves show very exaggerated peripheral falloff in sharpness. Nevertheless both lenses exhibit very similar behavior, very sharp centers wide open and even sharper centers stopped down.Another way of displaying the very sharp center character of both lenses.The Leica D Summilux sample image. ISO 200, f/1.4 1/5 second.The OM System Zuiko Digital 20mm f/1.4 PRO sample image.Again very similar image quality, one might show a touch more contrast and sharpness. Which one? This, BTW is a very traditional Chinese ivory carving but instead of using elephant tusk, this was carved from long dead mammoth tusk recovered from the melting permafrost in Mongolia. I’m so pleased to see this traditional industry change with the times to prevent the criminal killing of elephants in Africa. Mammoth ivory does carry a premium price but when I saw this piece in Shanghai in 2016, I did not give any consideration to price. Sadly, despite a lot of family connections in Shanghai including the house that my grandfather built and my father grew up in, this was likely my last trip to China. China is simply run by a reprehensible and lawless authoritarian regime. In 1938, would you buy products made in Nazi Germany if you knew about their death camps? The parallels are not an exaggeration.Which bokeh is more pleasing? This is a pin point source of light made by poking a pin sized hole through some heavy tape covering a flashlight. Which light source is more circular?Again which bokeh is more pleasing. Which has more contrast and sharpness such that even through the blur, the winery trademark is recognizable.
The Leica was right/left/left. By my tastes it seems to have the edge of performance over the Zuiko.
Vignetting at f/1.4 and f/4 with the Zuiko on the left, the Leica on the right. Stopping down reduces vignetting and again it seems the Leica suffers from less of it.
The Zuiko does focus faster and quieter. From the closest focusing position it focused on the ISO 11223 chart instanteously (recorded as 0.3 s) whereas the Leica took 0.9 s. But realistically both lenses focus fast and accurately.
In summary, the Leica is less expensive, allows you to proudly display the Leica name on the lens, and may produce the slightly more pleasing image (this being highly subjective). The Zuiko is lighter, smaller, quieter and weather sealed but more expensive.
I have degrees in Biochemistry and Dentistry and practice clinically 2 day a week. The rest of the week I devote to photography and bringing you the best writing in this blog.
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2 Comments
Ran the Pan-Leica for many years, gave the images I love the most. But eventually parted company, weather sealing became too important.
Informative write-up on the two lenses – quite surprised that the Olympus performance wide-open is off the pace in the corners. But as first poster says weather-sealing is a huge part of my choice for Olympus for my outdoors hiking or fishing in rain, saltwater spalshes and fish slime! My Zuiko 25mm f1.8 is used sparingly for low-light and/or bokeh situations.
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Ran the Pan-Leica for many years, gave the images I love the most. But eventually parted company, weather sealing became too important.
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Informative write-up on the two lenses – quite surprised that the Olympus performance wide-open is off the pace in the corners. But as first poster says weather-sealing is a huge part of my choice for Olympus for my outdoors hiking or fishing in rain, saltwater spalshes and fish slime! My Zuiko 25mm f1.8 is used sparingly for low-light and/or bokeh situations.
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