Soft left side FE 55/1.8 ?

[soowa]

Hi,

 

I recently noticed that my 55/1.8 might be somehow soft on the left side. Firstly, I noticed it on this photo: https://www.flickr.com/photos/125810262@N05/24234979239/sizes/o/ ( f/2.2 ) and then on some more after I concentrated on comparing left and right corners. I did a testing shot afterwards (two shots of the same chimney, first time in the top left corner, second time in the top right corner, aperture f/1.8, time was 1/800 or 1/1000, screenshots of raw files without any lens corrections and without any sharpening are attached). I know this not the proper way how to test a lens but it illustrates the issue. What do you think? Is this difference normal and am I too much of a pixel peeper, or should I claim warranty (the issue is not noticable on the first sight, and the image quality is still good, but on the other hand, the lens is quite expensive and I would expect more even sharpness).

 

edit: Hmm, the image was scaled down by the forum, so here is a link for the full size image of the comparison - https://www.dropbox.com/s/u9tbfavfmk86f6o/kresba.jpg?dl=0

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[Golem]

Hard to judge due the exposure difference

[dcisive]

looks to me like a clearly decentered lens. The one I have is sharp at BOTH sides even wide open and surgically so by f2.8. I would certainly try to replace it as this is supposed to be about their finest lens they make regarding the consistency of sharpness all over.

[EDBR]

Same problem with mine, also left side.

Maybe I will have to return the lens, any others with same problem.

Decentering ?

[soowa]

So, I did another test (still not scientific enough since I dont have test chart). Prefocused on an antenna on a nearby building and shot some test shots with various aperture setting to compare left and right side.

Although the issue is less pronounced here, it is visible, that there is a difference on f/1.8 and f/2.8. On f/4.5, both sides look the same to me. Again, they are 100% crops without any sharpening at all.

https://www.dropbox.com/s/wsk89dhsazxn8wm/kresba2.png?dl=0

It seems like that for apertures, where I need sharp corners, the sharpness on the left side is OK. However, I feel I should expect more from this lens - the left corner is also darker on f/1.8 although I set the exposure manually, which means uneven vignetting, so it really seems like decentering to me. (?)