I recently purchased a Canon EOS Rebel T1i, and I am trying to use a memory card that I had for my old Sony Lumix digital camera. I'm not sure if this matters, but the memory card is a SanDisk, and it holds 512MB. Is that memory card compatible with the Canon? If so, is there anyway I can clear our the memory card? I'm kind of a newbie at this, so any advice would be helpful. 
