I need to build myself a portable blind, and was planning on PVC tube for the frame, so I can pull it apart and assemble in the field.

I then realized I didn't really know how wide to build it. I'm quite new to this, so I don't really have much experience to use to judge it.

Does 12 feet wide, 4ft tall and 4ft deep sound reasonable for 3 people and my retriever? I was thinking a box shape with a bit of a roof angled up over our heads from the back.