As the title says, I found a recurring smudge in my photos when I was editing this one. You can see the smudge in the middle of the photo.
At first I thought it was on the outside of the lens, so I cleaned it off. Still there.
I ran the “clean image sensor” program on the camera. Still there.
So I detached the lens from my camera body and when looking through it with the aperture wide open, I could see the particle that was causing the smudges.
I then took a photo of a white wall with the flash on at the widest aperture setting I could (f/36) which I will be posting at the bottom of this post body. There the middle smudge and a smaller smudge in the lower left can be seen.
Is there anything I can do to resolve this? I can see there are 3 screws at the camera side of the lens that I might be able to unscrew, but I have no idea what’s inside or how complex it would be to pick apart. It wouldn’t surprise me if I just introduced more dirt by opening it up.
The smudge is very visible at any aperture setting greater than about f/6.
I appreciate any feedback.
Photo of a white wall:
Aperature is 1/number, so larger numbers = smaller aperature opening = less light coming through a lens. I agree with the others, you probably have something on your sensor. You might have something on one of the rear elements that’s causing this, but it’s less likely IMO.
Take a look at this pair of informative, and very amusing, posts over on lens rentals talking about dust in lenses.
https://wordpress.lensrentals.com/blog/2011/08/the-apocalypse-of-lens-dust/ https://www.lensrentals.com/blog/2015/06/i-dont-know-why-it-swallowed-a-fly-weather-sealed-lens-with-a-fly-inside/