Sony E 18-135mm f/3.5-5.6 OSS vs Sony FE 85mm f/1.8

The Sony E 18-135mm f/3.5-5.6 OSS is a zoom (18-135mm) and the Sony FE 85mm f/1.8 is an 85mm prime. The zoom gives you framing flexibility from one lens; the prime trades that for a fixed focal length that's usually brighter (f/1.8 vs f/3.5) and lighter to carry. Choose flexibility or a fast single focal length.

Choose the Sony E 18-135mm f/3.5-5.6 OSS if you need more reach — it goes to 135mm vs 85mm for distant subjects, wildlife and sport. Choose it if you shoot wide — it starts at 18mm vs 85mm for landscapes, interiors and architecture. Choose it if you want one-lens flexibility — a 18-135mm zoom covers what the fixed 85mm can't reframe. Choose it if you shoot handheld or on an unstabilised body — it has optical stabilisation, the other doesn't.

Choose the Sony FE 85mm f/1.8 if you want more light and background blur — f/1.8 is faster than f/3.5, better for low light and subject separation. Choose it if you prefer a fast, compact single focal length — an 85mm prime over a zoom. Choose it if you work outdoors — it's weather-sealed against dust and moisture; the other isn't.

Aperture: the Sony FE 85mm f/1.8 opens to f/1.8 vs the Sony E 18-135mm f/3.5-5.6 OSS's f/3.5 — more light and shallower depth-of-field.