This is something I was playing around with last night, learning to create reflections in water. I added the moon above the trees, and then added another layer with a mirror image of the moon as a reflection. With the reflection layer, I adjusted the opacity and added a bit of motion blur, and then skewed the perspective just a bit. Something about it just doesn't "fit" to me, though. I'd really appreciate some advice/cc to get this right.
A couple of thoughts that I have instantly. I feel the reflections too sharp. There's ripples in the water but not in the reflection. I would be grabbing the smudge tool and just running it back and forth through the reflection to give the impression that there's ripples running through it. That way it won't have an even edge.
Given the perspective of looking across the water I feel you'd alter the perspective of the reflection even more than you have. I would most likely be distorting the image to make it a bit shorter and also a bit wider at the top.
I also feel the opacity may not be quite right. The reflection covers an area where there's some light water and some darker water. It will reflect more strongly in the dark water than the light.
Lastly the moon above the trees is emitting no radiance. I feel it should be having a glow effect. That glow should then be in the water as well. I think it feels off to me without that.
Great advice! For the reflection, I changed the perspective and added the ripples. This made a big difference. Thank you!