Often, while hiking, my companions and I treat the very early/late sun as being less harmful (as far as skin cancer and UV radiation are concerned). For example, we might not apply sunscreen immediately after waking, but only after an hour or so, or skip putting on another round of sunscreen if it's relatively late (say, an hour before sunset).
My question is- is the sun less dangerous at these times? Is this bad for us? We don't backpack/hike that often, so it's not a very common occurrence, and it hasn't led to sunburn as far as I know. But I would like to know if there is gradual damage being caused to my skin.
I asked this related question on the Fitness Stack Exchange, but it doesn't seem to be getting the attention (or answers) I'd like.