Sony 10-18 lens weirdness

[sdwilsonsct]

There is a small gray rainbow just above centre in this image.

It appears in every sky image. It started just last week, and only with this lens. Camera: Sony a6000.

I can't see anything on the lens surfaces or the sensor.

Thoughts?

[E.J. Peiker]

That's some crud on the sensor.  It tends to be more visible with wide angle lenses, especially when stopped down.  You may not be able to see it without a bright light and loupe on the sensor.  Simply clean the sensor and it will go away.

[sdwilsonsct]

That's some crud on the sensor.

Thank you.