For the most part water reflections are darker than the object that it reflects. This is also true with transparent water. What we see under water in nature is darker and murkier which makes edges of what we see softer and not so dominant. The values will actually be very similar if not mostly the same. It is the colour of the object that makes it seem lighter when laid against another because if we were to squint at what we see under water, the values would be generally the same. If I get my values correct we should be able to see transparent water, reflections and shadow across this water.
Sorry if I am confusing you as what I consider I know in my own head isn't something I find easy to write down.
I think there is going to be a lot more head scratching over the next day or so to really nail this work.
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