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07-24-2016, 02:04 AM   #1
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hd da 70 2.4 limited- decentered?

Is this lens ok? I think that in full preview, extreme left side is worse than right side. Samples f5.6 - all walls and all trees (on last photo) should be in deph of field - https://www.dropbox.com/sh/l5gp6tz5a53kekj/AABRvDA4ZE3-Ao5x4RjSNkhia?dl=0

The second problem is that the barrel is loose.
I hear knocking when I gently shake lens - is that normal (new lens)? should I send back the lens?

07-24-2016, 04:32 AM   #2
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I can't tell for sure if there is a problem there from those images, I have seen threads on testing for lens decentering and can't find a link right now. For the tiled image it looks softer on the top left side.

On handling my copy of this lens, if I shake it gently I can hear movement, there is perhaps 0.5 mm (.02") rocking movement* (not measured) between the barrel and the body and a slight movement between the knurled distance ring and the body so there are two sources for the sounds heard. The movements are the same for min and max focal distance.
Hope this helps.

*With hood attached

Last edited by Kevin B123; 07-24-2016 at 04:33 AM. Reason: Completeness
07-24-2016, 06:18 AM   #3
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QuoteOriginally posted by raf7 Quote
Is this lens ok? I think that in full preview, extreme left side is worse than right side. Samples f5.6 - all walls and all trees (on last photo) should be in deph of field - https://www.dropbox.com/sh/l5gp6tz5a53kekj/AABRvDA4ZE3-Ao5x4RjSNkhia?dl=0

The second problem is that the barrel is loose.
I hear knocking when I gently shake lens - is that normal (new lens)? should I send back the lens?
I have an SMC version of the DA 70 Limited that I bought used in like new condition. It has the same knocking or clicking sound, especially when the inner barrel is fully extended. There is no impact on picture quality, it is one of my sharpest lenses, but the wobble certainly takes away from the stellar impression of Limited build quality. The wobble is more noticeable with the hood and cap on which probably makes the inner barrel more front heavy. Although there is a wobble in the inner barrel (the part that moved in and out) the focusing ring and the rest of the lens is tightly assembled with no other looseness. I noted this in my review in the lens database for this lens. From what I see in this forum, this one of the limiteds seems to be the most prone to this issue, so it seems you will notice it sooner or later. That said, I would not expect a brand new lens to be loose like this. My thought, send it back and exchange for another. Also, see how others weigh in on this topic. I thought of sending mine in for repair of the wobble but held back since pictures are just fine with my copy. I agree the left side of your pictures looks a little less sharp but I cannot tell if it is a problem with the lens or the angle of how you were holding it.

Last edited by jddwoods; 07-24-2016 at 06:23 AM. Reason: correct typo.
07-24-2016, 09:05 AM   #4
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I have that lens, the hd 70, and it makes a very slight clicking sound when I shake it. This is when it's focused to infinity, I guess it could be because the aperture lever is not engaged as when it's on the camera (?). I am fairly confident my copy is in good shape and this is normal.

I can't see much difference between the left and right sides in your examples btw, especially in the one with the building it might just be the difference in how bright the sky is. But there are some tests for decentering that you can do with just a computer, for example: Photozone - Do-it-yourself centering sanity check - Just Talk - Just make sure the camera is far enough away from the display.

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