Ghost Spots

[wfFoto]

Recently purchased a 100-400 for my a9. Looking at the lens head on, I see what appears to be, three square (ish) spots on the lens so I grab a "cloth" and brush it. Nothing. I spray said cloth and do a light rub. Nothing. I determine there is nothing on the exterior glass. I zoom and the spots disappear. To be clear...spots are visible @ 100mm. As I zoom to 400 they disappear. Photos, as of yet, haven't been noticeably affected. Anyone seen and/or know about this? Thinking of returning it.

Thanks

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[XKAES]

They look like reflections -- like the three other dots on the top.  They will move and disappear as you zoom because the elements move as you zoom.  Find something more important to worry about, like global warming.

[LiveShots]

If you look at the lens front-on and zoom in and out you will see that the lens right behind the front lens moves, so you will see reflections on that front lens that you won’t see when it’s further away from the front element.

Best way to check for dust/dirt on the lens or sensor is to aim the camera at a light colored wall and select the smallest aperture. Take a photo and check it, if there are dust/spots on the lens or sensor then they will be most visible at a small aperture.

I don’t think you have any worries with this lens, and even less worries about global warming; Earth’s temperature has fluctuated for millions of years due to changes in atmospheric pressure and cosmic radiation.

[XKAES]

And where did you get your university degree in climatology?  Trump University, perhaps???

I worry MUCH more about Global Warming -- as all climatologist do -- than I do about my photo gear.  It doesn't matter a HOOT about what you lug on your shoulder if it's too hot outside to take pictures -- like today!!!  I'm glad I'm not in Phoenix!!!

And now back to the question at hand -- do some tests.

Edited June 12, 2021 by XKAES