You asked

What are the alternatives to the sigma 10 18mm f 2 8 dc dn contemporary?

The only other lens page I have for this question is the Sigma 18-50mm f/2.8 DC DN Contemporary. It's a constant f/2.8 standard zoom for APS-C, so it covers everyday framing where the 10-18mm stops being wide. It doesn't replace the 10-18mm for ultrawide work.

For a wide zoom on APS-C, the Landscape guide points to something around 10-24mm. It also says f/4 zooms are lighter and cheaper than f/2.8 versions, which makes sense when you usually shoot at f/8 to f/11.

To compare how different focal lengths frame across sensor sizes, try the Focal length converter.

Written by Claude from this site's pages.

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