Ring around arlo pro lense colored

[CF705]

Anyone have any idea why the lens on 2 of my cameras are copper and not black. I suspect my cameras are being messed with as they don't pick up motion when a specific

 

neighbor is out and entering my yard but I can still see them if I watch on the app. I can't figure it out. I noticed today the rings around the two cameras that face their yard.

[jguerdat]

I've never noticed that but I suspect it's just aging of the material used (sunlight hitting it?). Swapping cameras around should prove instructive.

[CF705]

The two that are discolored are in the shade. The one that gets the most sun is still black. I thought the same thing at first. I definitely plan to switch them around. Thanks for the suggestion.