I bought this lens about a month ago and I've happy with the features this lens has to offer and the crisp image it produces

Need an excellent all-around lens to capture your stories This high-performance zoom was made for you. Many Olympus Visionaries and other professionals consider the M.Zuiko ED 12-40mm f2.8 PRO an indispensable piece of equipment.

I love this12-40mm f/2.8 lens! With a constant f/2.8 maximum aperture, I can take available light photos that previously would have required use of a flash. And, the photos at all focal lengths are noticeably sharper than what I was accustomed to with my previous lens.

I bought this because it's received great reviews and I wanted to replace my kit lens, but after getting it, I returned the Olympus 12-40 2.8. Let me explain with some pros and cons.

The image quality is great and the focus ring is fantastic, as you can change easily between manual and auto focus. So if you're trying to take a macro picture and focus goes to infinity, you just pull focus back to a near point and auto focus finds the focus point nearby.

This lens is so versatile I feel like it's a must have lens for any micro 4/3 shooter even if you're not a pro (I'm certainly not). The focal range is fantastic, that extra 5mm on the long end versus a traditional 12-35 makes it a viable portrait lens in a pinch.

I like this lens as my walk around lens. It is light and fun to use. Great package with the E-M1. Optically it is mostly good apart from the issue with ghosting and flares.

- perfect size and weight for my E-M1; sharp (I have never noticed the tested weakness in resolution at 40mm in real world); fast AF; water resistant (after about one hour in moderate rain and humidity at about 100% the lens became foggy from the inside and after half an hour in my bag it was ok...

Work with bright light sources in the frame; If you have bright light sources in the frame (e.g; candles at night) they cause annoying ghosting and flares; I hate this this behavior in the dark; In daylight it is usually acceptable.

I purchased this lens to go with the Panasonic GH4, I chose this lens over the Panasonic Lumix G X Vario 12-35mm f/2.8. The reason for that is build quality. The Olympus lens is all around metal and feels really well built.

This is the second best lens I have owned in almost 50 years of photography. The best is its companion 40-150 F2.8 Pro lens. A little larger and heavier then some m4/3 lenses but not so much as to be a problem for me. Optical quality is great at all focal lengths from F2.8 through F8.0.

Fast; well built; close focusing; weather resistant; sharp

EDIT: Thought of one; The auto manual clutched focus ring can be a little loose; Easy to bump it from auto focus to mechanical manual focus; Minor issue but I've done it a few times; Would be nice if it was a little stiffer to pull back

I always find the wide angle lens purchase so difficult a decision. I have used the Panasonic 14-45mm as my general purpose lens since the G1 was released. And more recently on the OMD series camera bodies.

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