Gufufoss, Iceland

[Falstaff]

That is a very nice collection of shots. You are only moving Iceland up my list (been toying with a trip as soon as next year, but we'll see).

You posted the photo under "image critique".....so, I thought I would take a stab at it. Mind the fact that I agree with the others, it is a very good shot and so much of this is personal preference/monitor calibration/etc.

But, a couple of comments:

1. The level is a bit off to my eye. This can make certain ribbons of water seem like they are falling unnaturally. I'd say only a degree or so (adjusted 1.5 degrees below, which may be too much).
2. As for composition, I wonder what the image would have been like a few steps to your left and lower. Have the river lead you to the water fall (Top center placement of waterfalls is tough).
3. Timing is a matter of choice, and here there are massive trade offs. I really like the 15 secs on the river, for the falls, I wonder what less time would looked like. Sometimes (certainly not always) when looking at a falls, I try to time the water as it falls and match that in my exposure. That way the final image is a single "arc" of water falling and not multiple which can impede the definition of the falls.
4. Greens, shadows, and sharpening seem a bit intense to me.

So, of course, I took a stab at implementing these changes.

Edits can be seen here:

Thanks so much for the feedback. I'm going to play around with your suggestions and let you know how it turns out. I haven't had the chance to get a proper display and have it calibrated, so I've always know that my colours and lighting will be off to some degree.