I generally just use an A frame. The 8X 10 is great and provides plenty of rain protection in that setup, especially if you are solo. However, that trapezoid under a tree looks pretty good. I have sat in a lot of rain storms in the rockies under a big pine and have been dry the whole time. The tree itself keeps a lot of water from hitting you. Putting the tarp up against the tree with make it even better, and still maintain good condensation control. I need to try it out.
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