2014年10月29日 星期三

Olympus M.Zuiko 45mm F1.8 test and Review (English version)


中文版請點擊這裡.

Introduction:
Olympus announced this 45mm lens(equivalent 90mm in 135 film system) at end of 2011. This focal length seems to match the portrait requirement. How about the appearance, touching, build and performance of this lens? Here is our report.


 Olympus M.Zuiko 45mm F1.8 outlook


 Specification of M.Zuiko 45mm F1.8


The optic:
As we can see the optic is 9 elements in 8 groups included 2 extra high refractive index elements(purple one) to correct high spherical aberration. The MTF point out the resolution character is very good, not only the sagittal but also the tangential. Not like the general lenses the tangential resolution(dashed line) even better than the sagittal resolution. Base on this MTF we think the resolution and sharpness of this lens must be excellent. Later you will know that by our test result. (If you don’t well know about the MTF you can refer this “Resolution and MTF curves in film and lenses”.)

 Optical construction of M.Zuiko 45mm F1.8


MTF of M.Zuiko 45mm F1.8


First Impresion:
This lens is impressive tiny for a 90mm fast lens. You can’t find another tiny fast telescop lens like this we promise. There are black and silver version of M.Zuiko 45mm F1.8 in the marker. All are plastic shell include focal ring. The silver one has obviously color difference with silver camera body(E-PL6). Thank God the mount is made of metal. The filter thread is in a standard 37mm diameter and 0.75mm pitch. Deco ring has a little loos must be careful to drop when mounting and un-mounting lens. Focal ring is well damped and have no trouble at manual focusing. While in auto focusing mode the in focus speed is very fast and quiet. A tiny lens mount to a tiny camera body(E-PL6) looks very decent and beautiful .

 Olympus M.Zuiko 45mm F1.8 on E-PL6


Test Start:
Some of the test results will be compare with the other lens with similar focal length. If you want to know about the test detail and procedure please refer to “Basic of lens test on Olympus E-PL6”.

Vignetting:
A very rare corner light loss at maximum iris, under 0.3EV. And the vignetting disappear after F/2.8. We rank it “Excellent”.

 F1.8

 F2.8

 F/5.6


 Vignetting of Panasonic G Vario 14-45mm at 45mm F/5.6


Distortion:
A very little pincushion distortion. We rank it “Good”.

 Distortion of M.Zuiko 45mm F1.8


Distortion of Panasonic G Vario 14-45mm at 45mm


Resolution:
Here is the sagittal and tangential resolution at center on F/1.8  F/2.8  F/5.6  F/8  F/11 (from left to right). The optimum resolution is at F/5.6. At maximum iris F/1.8 and F/11 have a little detail loss. The overall resolution are very good from F/2.8 to F/8.


Center sagittal resolution



 Center tangential resolution

Here is the sagittal(left) and tangential(right) resolution on F5.6 at 1/4, 2/4 and 3/4 from the center. Over all of the frame the resolution is very good. Not only the sagittal but also the tangential. This test result is just match to the MTF chart release from Olympus.


1/4 from center

2/4 from center

 3/4 from center



Corner resolution on F/5.6

To sum up the test result of resolution. We rank it in “Excellent”. This result is the best that we had ever tested. It is vary rare in M4/3 lens.

 Corner resolution of Panasonic G Vario 14-45mm at 45mm


Chromatic:
Here is the chromatic result at corner on F/1.8, F/2.8, F/5.6, F/8 and F/11(from left to right). Only at maximun iris have little red fring. We rank it in “Excellent”.




Flare:
Here is the flare under indoor spot light source.



Sun Star:
Here are the sun star under the indoor simulation light source. Due to the shape and edge of stars are very smooth all over the frame. We rank it in “Excellent”.








Sun star at indoor simulation of M.Zuiko 45mm F1.8


Sun star at indoor simulation of Panasonic G Vario 14-45mm on 45mm


Coma Aberration:
Have no coma aberration. We Rank it in “Excellent”.

 Coma at center(left) and corner(right).


Magnification:
The magnification of this lens is (17.3mm/140mm)=0.12



Details of picture:
Here are the detail on F/1.8, F/5.6 and F/22. There are a little detail loss on maximum iris.

 F/1.8

 F/5.6

 F/22


Defocus Aberration or Bokeh:
Here are the bokeh on F/1.8, F/2.8, F/5.6 and F/11. It is very beautiful. 

 F/1.8

 F/2.8

 F/5.6

F/11


Conclusion:
This lens has very good optical quality in each item:

Vignetting: “Excellent”
Distortion: “Good”
Resolution: “Excellent”
Chromatic: “Excellent”
Sun star: “Excellent”
Coma: “Excellent”

To sum up the test results, we rank this lens “Olympus M.Zuiko 45mm F1.8” in “Excellent”.

This lens retail price on Amazon is US$310. Due to the excellent quality and reasonable price, we give this lens the best buy of the M4/3 prime lenses. 

More sample pictures is at "Olympus M.Zuiko 45mm F1.8 Sample Pictures".

2 則留言:

  1. I found your blog today and I like it very very much

    your style is super readable and understandable for beginer like me

    good job..keep going and support awesome m43 format

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    1. Thanks for your reply. I am happy that you like my post. Due to the English is not my mother language so I don't have much post in English. Anyway, I will do my best for that.

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