Lens review

Olympus Zuiko Digital 25 mm f/2.8

4. Image resolution

The Olympus ZD 2.8/25 was tested by using the RAW files and an E-3 reflex camera. A connection between the MTF 50 function value and the aperture in the frame corner and in the frame center is presented in the picture below.

The frame center performance is very good. Even at maximum relative aperture the pictures are of good quality. Of course the cheap ZD 2.8/25 is no match for an expensive Leica with the same focal length. The Leica by f/2.0 is sharper than the Olympus at the height of its abilities, by f/5.6. The comparison with the Olympus ZD 3.5/35 Macro from the similar price shelf shows a minimal (within the margin of error) advantage of the “pancake”.

A totally different situation can be noticed for the frame edge. Here the Olympus ZD 3.5/35 wins and the “pancake” and the Leica are significantly weaker. What’s more interesting, by f/2.8 the ZD 2.8/25 is even a tad sharper than the Leica.

To sum up, the tested lens’s frame edge performance can be described as good, but certainly not very good.

At the end we present the test chart excerpts, obtained from the JPEG files by f/2.8 and f/5.6 apertures.