Panasonic 25mm F1.7 vs. Mitakon 25mm F0.95 sharpness comparison: Both lenses are fast “normal focal length” lenses released in 2015 for the Micro Four Thirds System (MFT). While the Panasonic Lumix G 25mm F1.7 is the cheapest 25mm lens available for the system, the ZY Optics Mitakon Speedmaster 25mm f0.95 is the cheapest F/0.05 lens available.
Panasonic 25mm F1.7 vs. Mitakon 25mm F0.95: Test Procedure
For this test I mounted my OM-D on a tripod and released the shutter via the Olympus app on my phone. The camera was set to electronic shutter, IS off and ISO 200. I took 5 pictures with refocusing for every setting and chose the best of these pictures to avoid focusing errors. I also took separate pictures for the image border to make sure it is perfectly in focus. All images where shot in RAW and exported to JPG with DxO Optics Pro and the setting “No corrections”, which means they are less sharp than out-of-camera JPGs would be. All images are of course 100% crops.
Comment: Transmission of the ZY Optics Mitakon 25mm Speedmaster f0.95
Prior to the release of the ZY Optics Mitakon 25mm Speedmaster f0.95 there have been rumors that it’s real light transmission (“T-stop”) might be lower than it’s theoretical light transmission (“F-stop”). Therefore I made some comparison images to test the light transmission and looked at the shutter speeds the camera reported at maximum aperture. In my review of the Panasonic 24mm F1.7 I concluded that it most likely has a T-stop of T/1.8. At maximum aperture the Mitakon 25mm F0.95 1 to 1,5 stops faster than the Panasonic. It seems that the Mitakon 25mm F0.95 is on average 1 1/3 stops faster than the Panasonic 25mm. Therefore it seems that the ZY Optics Mitakon 25mm Speedmaster f0.95 is an T/1.2 lens. However these are only estimates.
Mitakon 25mm F0.95 @ F/0.95
Panasonic 25mm F1.7 vs. Mitakon 25mm F0.95 @ F/1.7
Panasonic 25mm F1.7 vs. Mitakon 25mm F0.95 @ F/2.8
Panasonic 25mm F1.7 vs. Mitakon 25mm F0.95 @ F/5.6
Panasonic 25mm F1.7 vs. Mitakon 25mm f0.95 – Conclusion
I already tested the sharpness of the Panasonic Lumix G 25mm F1.7 and concluded that it is a sharp lens, especially at the image center. How fares the ZY Optics Mitakon 25mm Speedmaster f0.95 in comparison?
The results at the image center are sensational! At F0.95 the Mitakon 25mm f0.95 is already as sharp as the Panasonic 25mm at F/2.8. Stepping the lens down further improves sharpness. If both lenses are set to F/5.6, the Mitakon 25mm F0.95 is clearly the winner regarding sharpness – and the Panasonic 25mm F1.7 is already very sharp at F/5.6.
The result at the image border is a bit more complicated: At F/0.95 the images borders are rather soft, but that is to be expected from an F/0.95 lens. At the F/1.7 they are already much sharpers. The ZY Optics Mitakon 25mm Speedmaster f0.95 is even a tiny bit sharper than the Panasonic Lumix G 25mm F/1.7 at F/1.7. If both lenses are set to F/2.8 the border of the Mitakon 25mm F0.95 are again a tiny bit sharper. At F/5.6 it is hard to say which lens is sharper.
Both lenses take very sharp pictures and can be complimented for their sharpness. I am really impressed by the performance of the Mitakon 25mm F0.95! I did not expect a cheap lens from China to be so sharp!
Mitakon 25mm f0.95 – Field Curvature
Other reviews of the ZY Optics Mitakon 25mm Speedmaster f.095 are less favorable. Those reviews claim that the border of the Mitakon are extremely soft and that they do not improve if stepped down to F/2. These tests claim that you have to step the lens down to about F/5.6 to get decent results at the image borders. As you can see for yourself if you look at my test pictures this is not true. The corners improve a lot if they are stepped down to F/1.7 and are already at a good level at F/2.8. So what is the explanation of such different results?
The only reason I can think of it that the others reviews did not take the field curvature into account. Field curvature means that the image center and image borders have different focal points. It seems they focused on the image center of a plain test chart and took the results for the image borders from the same image instead of refocusing for the borders. As the Mitakon 25mm f0.95 has a strong field curvature wide open this means the image borders were out of focus.
In my opinion the field curvature is not a big problem in real life shooting. How often do you take pictures of a frame filling flat object at F0.95? If you step the lens down to F/8 the field curvature effect is gone.
In my opinion there are two reasons to take pictures at maximum aperture:
a) To isolate an object. In this case extra blur in the others areas of the images is a good thing.
b) To take pictures of moving objects in low light. In this case the objectiv will seldom fill the whole picture and therefore you will most likely not notice the field curvature.
If you take the field curvature of the lens into account, as I see it, it will seldom be a problem.
At the moment the ZY Optics Mitakon Speedmaster 25mm f0.95 is only