This is a nice composition. It also works well as an abstract. There is tension of opposing forces that you feel. Is the left moving towards the right or right towards the left. Lots of energy here. I see this more as leaning towards abstraction rather than a representation of water.
João, this is a great view of this rapid. I like how you’ve split the frame roughly in half and am impressed that you’ve got similar sharpness from bottom to top. This is a nicely meditative view where I can hear the sounds of the rapids as I enjoy the sense of movement in the water.
There is something in the nature of moving water that I have called dynamic invariance. By which I mean that which is constantly changing while at the same time always remaining the same. You have captured this beautifully in this image. But what makes it special for me is what @Igor_Doncov has pointed out, namely the opposition of dark and light. There is a dynamic balance in this image that gives it a lot of power but also a sense of repose that I can meditatively sit with. Beautifully composed.
I really like how you pulled this image together both in the field and in processing - just a thing of beauty. Perfect shutter speed and handling of the luminosity range. Superb.
I really like this. As a print, it would catch my eye across the room. Aesthetically, it grabs my attention. Light versus dark. Rough versus smooth. Very well balanced composition! Technically, I think you did a great job on your choice of location and getting it all in focus, and in keeping all the tones there. Awesome!