I'm an amateur photographer and only just picked up my first DSLR (went for a 50D with a basic 18-55mm Canon IS lens) and was considering purchasing a wider angle lens such as the Sigma 28mm f/1.8-22 for around $400 AUD, or a Canon EF 28mm f/2.8 for a little less to allow me to take photos of groups of people in rooms and buildings without breaking the bank.
I'm in a band and we'll be recording early next year and I thought I would get a moderately cheap wide angle lens to be able to take photos in studio-sized rooms (often small) and venues in particular where a wide FOV would give me room to breathe.
Am I correct in assuming these would be the types of lenses that would work well in these more enclosed spaces? Would a prime lens be the way to go for this?
Would they also be usable for outdoor short DOF shots (such as nature macro shots)?
Thanks for any advice you can give me.