I was trying to use my "nifty fifty" and 550EX last night to take pics of the trick-r-treaters and ran into a problem. I had the 550EX set to auto and ETTL and got nothing but SLOW shutter speeds at 1.8. I tried and number of differing stops and generally got the same result each time. When I couldn't figure out what was going on I changed to the 28-135 IS lens and it worked fine. Did I miss something with the 50? Thanks.
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