The two crop-specific offerings from Canon are the EF-S 60mm f/2.8 Macro USM and EF-S 35mm f/2.8 Macro IS STM. They're both on the affordable end of the price range, both feature f/2.8 as maximum aperature, and both offer 1:1 magnification, so I'm trying to figure out what differentiates the two that I can make a decision based on.

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