Leaks in holders will always show at the edge of the image. There's no way for there to be a leak in the middle of the image and not along the side. The light would travel in from the edge with a holder leak, so the streak you're showing in the first image cannot be from the holder.
It doesn't look like lens flare either, which happens in round shapes typically, and also is usually found at an edge. The shadows don't suggest that the camera was looking that closely into the sun anyway/
This looks to me like a seating problem with your back or bellows.
Bookmarks