You asked

What lenses should I buy for the sony a9?

The Sony a9 is full frame, so lenses frame exactly as marked, and the catalogue for it is long. If you don't have a particular subject yet, I'd start with three:

If you shoot mostly sport, the telephoto is the one to prioritise. If you're on a budget, the f/4 zooms on the same a9 page are worth a look. Before you commit, check the three questions on the home page. A lens mount lasts longer than a camera body, so think about the lenses you'll want in two years, not just today.

Written by Claude from this site's pages.

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