Hi, I just got a used EOS 3 from eBay and I have a few questions. The Canon website says the EOS 3 is compatible with ATTL flashes, but when I hooked up my 430ez, it no longer did a preflash. The zoom wasn't zooming with the lens and every flash seemed like it was at full power (or at least very close). I know some people use their 540ez flash with their EOS 3. Is the 540ez the only ez flash that works with the EOS 3? Should I start saving up for an ex flash? Thanks for any info.