Not a lot to say specifically about the m4/3 lenses except please don’t ask why your favorite isn’t on here; this is all I’ve got. Some of the newer m4/3 have linear electronic focusing which can’t be tested on the bench without a specialized, expensive mount and we don’t have one. Even for the ones I have here, many don’t have 10 copies. Micro 4/3 doesn’t rent as much as it used to and we don’t have the kind of stock that we do in other mounts.

A Quick How to on Reading MTF Charts

If you’re new here, you’ll see we have a scientific methodology to our approach, and use MTF charts to measure lens resolution and sharpness. All of our MTF charts test ten of the same lenses, and then we average out the results. MTF (or (or Modulation Transfer Function) Charts measure the optical potential of a lens by plotting the contrast and resolution of the lens from the center to the outer corners of the frame. An MTF chart has two axis, the y-axis (vertical) and the x-axis (horizontal).

The y-axis (vertical) measures how accurately the lens reproduces the object (sharpness), where 1.0 would be the theoretical “perfect lens”. The x-axis (horizontal) measures the distance from the center of a lens to the edges (measured in millimeters where 0mm represents the center, and 20mm represents the corner point). Generally, a lens has the greatest theoretical sharpness in the center, with the sharpness being reduced in the corners.

Tangential & Sagittal Lines

The graph then plots two sets of five different ranges. These sets are broken down into Tangential lines (solid lines on our graphs) and Sagittal (dotted lines on our graphs). Sagittal lines are a pattern where the lines are oriented parallel to a line through the center of the image. Tangential (or Meridonial)  lines are tested where the lines are aligned perpendicular to a line through the center of the image.

From there, the Sagittal and Tangential tests are done in 5 sets, started at 10 lines per millimeter (lp/mm), all the way up to 50 lines per millimeter (lp/mm). To put this in layman’s terms, the higher lp/mm measure how well the lens resolves fine detail. So, higher MTF is better than lower, and less separation of the sagittal and tangential lines are better than a lot of separation. Please keep in mind this is a simple introduction to MTF charts, for a more scientific explanation, feel free to read this article.

Olympus

Olympus M. Zuiko 12mm f/2.o

Lensrentals.com, 2019

Olympus M. Zuiko 17mm f1.2 PRO

Lensrentals.com, 2019

Olympus M. Zuiko 17mm f1.8

Lensrentals.com, 2019

Olympus M. Zuiko 25mm f1.2 Pro

Lensrentals.com, 2019

Olympus M. Zuiko 25mm f1.8

Lensrentals.com, 2019

Olympus M. Zuiko 45mm ED f1.2 Pro

Lensrentals.com, 2019

Olympus M. Zuiko 45mm f1.8

Lensrentals.com, 2019

Olympus M. Zuiko 75mm f1.8

Lensrentals.com, 2019

Panasonic

Panasonic DG Summilux ASPH 25mm f1.4

Lensrentals.com, 2019

Panasonic-Leica 42.5 Noctitron f1.2 

Lensrentals.com, 2019

Panasonic Lumix 42.5mm f1.7 OIS

Lensrentals.com, 2019

Panasonic-Leica DG Macro OIS 45mm f2.8

Lensrentals.com, 2019

Voigtlander

25mm f0.95 Type II

Lensrentals.com, 2019

42.5 f0.95 Aspherical

Lensrentals.com, 2019

For a look at all the Just MTF Articles we’ve done so far, be sure to check them out here

Roger Cicala, Aaron Closz, and Brandon Dube

Lensrentals.com

May 2019