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Is the sigma 12mm f 1 4 dc contemporary good for astrophotography?

I don't have anything on astrophotography, so I can't say whether this lens suits the night sky. The Sigma 12mm f/1.4 DC Contemporary page does give you the basics: a wide f/1.4 maximum aperture, about 18mm equivalent on APS-C, with autofocus and no stabilisation. A wide, fast lens is the kind of thing you'd look for in a night lens, but check dedicated astro reviews before you buy.

The closest page I have is landscape, which covers wide lenses for outdoor scenes.

Written by Claude from this site's pages.

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