If you’re looking for a compact zoom lens the Sigma 28-70mm f/2.8 DG DN Contemporary is hard to beat. Camera Size.com included the Sigma 28-70mm f/2.8 its latest update and the lens looks minuscule compared to the Sony 24-70mm f/2.8 GM. I personally would go for the Tamron 28-75mm f/2.8 or Sigma 24-70mm f/2.8, but if you want compact and Sigma the Sigma 28-70mm f/2.8 looks good.
SIGMA 28-70mm f/2.8 DG DN Contemporary:
B&H Photo / Amazon / Adorama
SIGMA 24-70mm F2.8 DG DN Art:
B&H Photo / Amazon / Adorama
Tamron 28-75mm f/2.8 Di III RXD FE:
B&H Photo / Amazon / Adorama
Sony FE 24-70mm f/2.8 GM:
B&H Photo / Amazon / Adorama
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