Best portrait lens for the olympus om d e m10 mark iv?

For portraits on the E-M10 Mark IV, the 85mm-equivalent range is the sweet spot, and the Micro Four Thirds lens list has several good options there:

• Panasonic Leica DG 42.5mm f/1.2: the fastest and most flattering choice, with the shallowest background blur.
• Olympus M.Zuiko 45mm f/1.8: a lighter, simpler lens that still gives you 90mm-equivalent framing.
• Panasonic Lumix G 42.5mm f/1.7: a compact alternative if you want something small.

Don't skip the light. Light beats gear is worth reading before you spend on glass. For more on where a portrait lens fits in your kit, see your first lenses.

Written by Claude from this site's pages.