The Sony FE 24-70mm F2.8 GM and Tamron 28-75mm f/2.8 Di III RXD lenses share a similar focal length, and both can be used with Sony's full frame mirrorless E-mount cameras. But they differ dramatically in price.
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Tamron 28-75mm F/2.8 Di III VXD G2 Review
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The Ultimate Mirrorless 24-70mm Comparison