What is the difference between a Canon EF lens and a CANON EF-S lens? - Yahoo Answers

Best Answer: All EF and EF-S lenses are compatible with the Ti. EF-S lenses are designed to be only used on dSLRs with an AP-C sized sensor (this includes the T1i, XSi, XS, etc. etc). However, full frame cameras (5D Mark II, etc) cannot use EF-S lenses. F

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