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Are these centered ?
#1
Here are a few images from two lenses. I'm trying to test if they are 'centered' or at least good enough that they do not need to be exchanged given their reputation. I'm having trouble with the test as pinned here mostly because I'm not sure I know what to look at (maybe a hint that I shouldn't be worried?).

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Here are a few images from the two lenses. The first few images were heavily under-exposed because I set the camera incorrectly. A few are intentionally a little out of focus because per instructions I thougt it would show the symmetry better. For the 18mm I was approx 2 feet from the screen; 50 mm I was 4 feet and 200mm I was approx 6 feet. With a bit of hassle I can back up further for the 200 mm. Naturally I can retake these images based off of feedback.

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#5 and #7 concern me the most but I suspect i am doing something fundamentally incorrect and I will have to hide my head in shame when I hear the comments.

#2
 I do a real world test using the lens wide open on distant infinity views of tree lines...... three images without change of focus with trees 1/top  2/middle and 3/bottom.........."you can never be out of square with Infinity".........it's also the most demanding at pixel level!...
#3
Ok. I guess I can try a couple of buildings (no trees here) when I get home and post them. I just thought hte chart above was suppose to be an easy way to identify major defect but either I did it incorrectly or it is more difficult then I thought. i feel stupid.

#4
One of the problems is posting here is limited in quality,  your images look OK to my eyes, but I wouldn't want to say one way or another on the strength of these compressed files, (for fear of being wrong).

 Besides anything else I have had lenses that looked great close up and looked awful at distance, I would only trust distant views for testing for centering, there's no point in temporarily satisfying yourself if you find out there's a problem a few months down the line!

 

 Others may think different however. 

#5
Ok here are some images @ infinity. What do you think ? The first image (heavily reduced) shows full frame; the second is fist top; third is first bot then repeat with 2nd set.

 

Appreciate comments.

#6
I'm sorry but with all my best will in the world I cannot get a grip of the sharpness in this way!  Can you not post a RAW image in "dropbox'?  that way I could stand a chance.............. otherwise it's a bit like doing resolution tests from facebook!
#7
Ok. Will try to post a raw tonight. I'm more concern about trying to figure out if the lens is reasonably centered. I'm begining to think if it is not cenettered it is close enough. Kind of wish Klaus could comment on how to do the oringal thing with the test pattern correctly but I suspect he is busy. Anyways will post a link to the raw tonight for the two images above.

#8
Ok I uploaded the raws  they are as follow:

 

 https://www.dropbox.com/s/x7sh6p8tc8udfc...2.RAF?dl=0

 

 https://www.dropbox.com/s/rzgw9upj8rk8ig...5.RAF?dl=0

 

Let me know if you have any issues. Note the exif data should be intact; they were taken wide open. I'm mostly concern about detecting lens decentering since Klaus has a greater than 50% issue with these lenses.

 

Thank you for your assistance.

#9
Hum. Any comments pretty please.

  


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