/.../Close Up Lenses used on a DSLR often fall short of expectation in respect of IMAGE QUALITY/.../
/.../ But for the cost of a Canon (or High Quality Hoya) CU lens . . . there will be not much difference to the cost of a good quality set of three Extension Tubes.
One main benefit of a set of Extension Tubes, compared to CU Lenses is the flexibility of magnification and working distance tubes will provide with a set of Lenses.
One main hindrance Tubes bring, is that for very close work the Viewfinder will dim.
With respect to Canon APS-C Cameras –
this thread will provide information.
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