Best telephoto lens for the sony a6000?

Here is what the site says about that.

From Sony a6000: Sony a6000: A mirrorless camera by Sony with a 24.3-megapixel APS-C sensor, announced in 2014. A long-running bestseller and a cheap used way into Sony APS-C. Specs - Maker: Sony - Mount: Sony E - Sensor: APS-C, 23.5 x 15.6mm, crop factor 1.5 - Resolution: 24.3 megapixels - Stabilisation: none in the body; use stabilised lenses for slow shutter speeds - Announced: 2014 - Type: mirrorless camera Focal lengths on it Lenses ...

From Sensor sizes: What it costs you: - Size, weight and price, especially of the lenses. A full-frame telephoto is much larger than its APS-C or Micro Four Thirds equivalent. - Less depth of field when you want more of it, for macro or landscape.

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