Olympus m.ZD 9-18mm f/4.0-5.6 lens

introduction

a Micro Four Thirds system version of the Olympus ZD 9-18mm consumer wide angle zoom for Olympus Four Thirds dSLR system
the most compact and light-weight ultra wide angle lens available for any system of this sensor size or larger
“an engineering masterpiece”
a handy travel, landscape lens offering ultra wide angle zoom covering 18-36mm in 35mm film terms whilst still allowing filters for landscape work
in-camera corrected distortion is mild at 1.8% at 9mm and minimal from 12-18mm BUT uncorrected the barrel distortion is a poor 4.8% at 9mm
uncorrected vignetting is mild at 1EV at f/4 9mm with in camera correction improving this to 0.7EV
very reasonable sharpness performance at all focal lengths and best at f/4-5.6 range
well controlled CA at < 0.7px
similar optical quality to Panasonic 7-14mm f/4 ultrawide zoom lens but smaller, and can use filters
similar optical quality to Olympus ZD 9-18mm Four Thirds lens but much smaller and faster AF
a worthy consideration for your travel kit but at $600 one needs to decide whether to go for the Olympus m.ZD 12mm f/2.0 lens which is $700 and although not a zoom lens, offers a much wider aperture, better image quality and better manual focus controls.

9-18mm focal length = 18-36mm in 35mm terms = ultra wide angle zoom for landscapes, travel, etc
closest focus 0.25m
filter 52mm non-rotating = great for polariser filters and ND gradient filters (but there may be some vignetting at widest angles)
7 rounded aperture blades
12 element, 8 group design utilizes two dual-surface aspheric elements to form the front cell, and ED and HR glass elements to combat CA
internal focusing
collapsible design with lock switch for transport keeps it safe and compact
fast and silent AF motor = very usable for HD videos
optional bayonet mount hood
57 x 50mm = very compact indeed although it does extend on zooming to 9mm
155g