A round shadow or ghost appears in the centre of the image

[eugeniofarri]

Hi Sony Community, 

I'm trying to understand something that started happening recently using my Sony A7IV + 100-400GM lens which I have used for the last 2  1/2 years. After a cold day in the snow recently, I have noticed a shadow in the centre of my photos and I don't see any solution online as to why this is happening. I can live with the usual vignette but this circle in the middle is bothering me a lot. 

I have attached the same photo (one over dehaze to accentuate the circle so it's very evident, and the others is for you to see that even with normal editing I can still see the circle (especially in the small thumbnail down in Lightroom Classic) I have tried removing the neutral filter from the lens, shooting settings, but it seems to be always there (at 400mm is more evident) 

Any one with the same issue?? 

 

[daveyh64]

Is it a lens problem or a camera problem.

Is this happening with other lenses.

Have you checked the cameras vignette setting to see if you may have inadvertently set a value

there that could be causing the issue.

[danardeng]

Actually the humidity is grabbed by a surface when the surface (lens) is cold, and is placed in a warm ambient (where the humidity rate is higher).

So, it could be happened.

I’m not sure that is this the case.

[eugeniofarri]

I actually haven't check with another lens. Will see what happens and get back to you. I haven't change the settings on the camera, I double check just now.

[danardeng]

If you suspect that there is humidity inside, you can try to place the lens without caps (so in a clean place) in a warm ambient, like near a heater. Be sure that it only warm the lens slowly.

At least the humidity should be vaporise and the circle effect should disappear. But it can return again when the lens returns in a cold climate.

[eugeniofarri]

Thank you so much, danardeng. I will try that asap and see if the situation improves. 

[danardeng]

Be careful, please don’t cook your lens 👨‍🍳