Thanks for the response. I suspect the same as you. I've never seen this before.
I have no idea what "high gain" refers to. Nothing special was done to this using Apple Photos.
I have a message in to Tamron and am trying to tweak certain things. Will let you know.
SonyA580 wrote:
I am thinking from the lack of comments that, like me, no one has seen this type of banding before. The only thing different I noticed going over the EXIF data was that "High Gain" was used somewhere in the process.