Here is a crop of that pipe-like object. I’m not convinced it is man made though. In fact, after studying the images further I find myself rethinking some of the objects I highlighted earlier, especially the shelf (red arrows) in the second image. I found another very similar feature toward the end of the video so I am no longer considering it man-made, although the reverse “C” and small box features still intrigue me.
Yes, that coral is tricky. The only experience I have at discerning coral from man-made stuff is what has been posted on this website. This must be the worst environment (other than say, a thermal vent) to search for 75 year old airplane parts in.
Without stirring up too much more debate, I also wanted to mention the “wheel” just down the slope in the video. I believe it is an illusion. I have nothing solid to prove it- it just seems to me to be awkward if you watch the video thinking it is a wheel and tire, even a deflated one. In the 3D rendering, it doesn’t have much depth, and I don’t see any hard border between the sand (or whatever you call the white stuff) and the object. Looks to me to be a shadow. That shadow part appears sunken in, but it might be just because there is no information there for the brain to interpret. Unfortunately the parallax is horrible in this image, even worse than the others. If you watch the video, as the ROV flies over the object, you get the impression that it is not very wide. Also the scale is off. If the object were 3 ft in diameter like an Electra wheel the ROV would have to be moving pretty quickly. I’d be very interested to know what Jeff or other experts see in the 3D images. Well worth the few bucks for the glasses IMHO.