In article ,
says...
No, the 18-70 is certainly NOT 'L' glass equivalent.

Which is the case - you don't know what the optical performance
of teh 18-70 is or you are deluding yourself about L glass quality?

"L" denotes better build quality and better optics. It also means a
hell of a lot more in terms of cost.

The 18-70 is a decent consumer zoom. But it is no where near the
quality/build of a 'L' series lens.
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