You asked

Is the pentax smc d fa macro 50mm f 2 8 good for video?

The site doesn't say how this lens performs for video. Its page covers the focal length, aperture, autofocus and which Pentax K bodies it fits, but nothing about video.

From what the page does say, it's a 50mm macro with no stabilisation. On APS-C bodies like the K-3 Mark III or KP it frames like about 75mm on full frame, which is tight for vlogging. My video guide suggests a wide lens, around 16-20mm full-frame equivalent, for talking to camera. A standard or short telephoto lens works better for filming a subject at a distance.

If you're shooting close-up or tabletop work, the lens may suit you, but check autofocus behaviour in video mode before you buy. And whatever lens you choose, budget for sound. The audio section covers the options.

Written by Claude from this site's pages.

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