Are there reasons beyond weight and price to choose the Olympus 40-150mm over the 14-150mm?

Question

I'm curious whether there is any advantage in buying the 40-150 vs. the 14-150 lens. Both are f/4.0-5.6 and quality seems to be the same.

Is there any reason except weight and price for which one would choose the 40-150?

Answer

The 40-150mm is optically better and lets you open to F/4 at 40mm, while the 14-150mm is already F/5.6 by that focal-length, so you get more light in until you get close to the end of the zoom range.

For sharpness, it depends which side of the 40-150mm range you prefer. At 40mm, the 14-150mm is noticeably sharper than the 40-150mm. At 150mm, the 40-150mm is noticeably sharper. See sharpness samples at all F-stops here and here

Vignetting is terrible on the 14-150mm at both ends of the zoom, while moderate on the 40-150mm and only near the widest aperture. The 40-150mm lens also shows less distortion.

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