I have been doing whitewater kayaking for some time now, and still have a great deal to learn. For difficult places, it is normal for me to stand outside and talk about which lines are good and which places to avoid. More experienced people can simply point out salient features to each other, "Go right after you have boofed over that ridge, with enough time to steer clear of the undercut rock". I am still at the stage where I have to learn how to recognize a barely visible ridge, to know where I will need to boof, to spot which one of the dozens of rocks is undercut.
As pointing with a finger only gets us so far, I thought of using a laser pointer. I even found a model which is waterproof (meant for divers). But I am reluctant to try it, as it is expensive enough to hurt if it turns out to be useless.
- if I get a laser pointer, will I be able to see the dot on the water surface?
- assuming that it works, what would be the minimal strength required to see the dot in direct sunlight?
- Again assuming that it works, which colors will work? I was surprised to read some diver mentioning that underwater, green is better than red, but have no idea if this will hold for the surface.
- The water surface reflects more like a mirror than like a random solid surface - will this be as damaging for the eyesight as having the pointer itself pointed directly at the eyes? Yes, the water is probably somewhat foamy, but it tends to have still places too.
- are there other potential problems with my idea?
- are there easier solutions to the same problem?
Update I am specifically asking about good methods for pointing, not for finding the line in other ways. I am more concerned with learning to read the water than with finding the perfect line. To those who don't know what it looks like, the following picture is a good example. The important thing in the picture are not the stones, but the shape and behavior of the water in the different (small) places between them.