RF 100-500 background distortion ? Please help

[ksmithson916]

I notice that most of my shots have this lateral line distortion in the foreground and background, is this a defective lens?

pics attrached

[jrhoffman75]

Hello.

Top photo looks there is a lot of reflection or something happening.

Is it always in the same location? Do you perhaps have something on the sensor?

What if you placed your subject in that location so that the subject is sharp and the problem would stand out better.

[Waddizzle · Accepted solution]

Are you using a UV or CPL filter?

[ksmithson916]

I was in fact using a fairly pricy $130 UV filter, removing it fixed the problem, thanks

[Tintype_18]

For future reference, how would the filter effect the photo? Thanks.

[Waddizzle]

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@Tintype_18 wrote:

For future reference, how would the filter effect the photo? Thanks.

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I cannot say with any certainty.  I have seen this before with my EF 100-400mm II. The sensor has a UV layer built into, but UV filters did not affect photos with other lenses.

Also, the aberrations were neither perfectly horizontal or vertical, which made me think that the issue was probably not the camera or the lens.  Removing the filter not only eliminated the aberrations, it also made the photos MUCH sharper.

[EDIT] Oh, yeah.  I use B+W Nano Clear filters on my lenses.  I do not use them for protection from impacts.  I use mainly use them to keep the front element clean.  

I have never had need to clean my front elements.  But, I frequently find myself cleaning the front filters.  I have to clean off smoke residue from BBQ cook offs, tree pollen from being in the woods, and fingerprints.  I am really sloppy when it comes to putting on a lens cap. 

[jrhoffman75]

Sometimes there can be reflections off the front element of the lens that bounce back to the rear surface of the filter. Good coatings should handle that, but not always.

[ksmithson916]

btw, I through on my other Zeiss brand UV filter with T coating and the problem was still resolved, it was just that brand of filter. I not only trust Zeiss UV filters.

[ebiggs1]

I am not seeing a lens problem beyond how it handles OOF BG. I suspect this BG aberration changes as your aperture changes?

I would also advise you remove any add-on filter you may have used.

[ksmithson916]

It did end up being the filter when I removed it all pics had perfect bokeh.