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.

It is big and heavy and operates buttery smooth. If you are looking for image quality close to the primes in this range, but would rather have weather sealing then this lens will get you closer to anything else on an Olympus camera.

Durable; Easy To Use; Reliable

Bulky

Micro 4/3's is not a very good at fast action photography, like sports or running children, this lens makes it more tolerable.

High quality piece of glass! Takes outstanding photos on my EM-5; Comes with a lens hood; This is truly a Pro lens

On the expensive side if your a novice

great lens with wide zoom range and fixed aperture throughout. Pictures appear to be very sharp, autofocus is very fast, good build quality (but lens extends when zooming). 62mm filter size.

fixed aperture; sharp images; weather sealed

lens extends with zoom

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.

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.

None

"I've had this lens for a while now and it is indeed everything you've heard about it: - Sharp: excellent a the wide end, very good at telephoto. Good enough so that I'm not constantly fumbling for my prime when I want *sharp* photos - Rugged: Beautiful metal finish shouts ""Quality"" and...

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 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.

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