The stuff you can see is the uppermost layer in my composited scene.
The grey and white checker board pattern is Photoshop’s way of telling me that part of the image is completely empty, which means it’s going to reveal whatever layer I put underneath.
At this stage, I’ve put a render of sand and pebbles underneath the foreground layer. So the eye interprets it as being behind the boat. It looks like the sand goes on forever, which is just the impression I want to make. I’ll put a layer of water over it next.
Here’s the water. The water is hiding the sand beneath it because you can’t see through it yet. So it’s time to use some of the power of Photoshop …
I’ve made the water transparent at the bottom of the picture going up to not-transparent at the top. You can judge the amount of transparency by how much of that grey checker board pattern you can see through it.
In the next step we won’t be seeing grey checker board through the water. We’ll be seeing sand.
… And here’s the sand seen through that semi-transparent water. This was really quick — only about ten seconds of ‘work’ to get this effect. That’s why I chose this method instead of making it all happen in the 3D program. As much as I love 3D, I love my time even more!