Olympus M.ZUIKO Digital ED 100-400MM F/5-6.3 is Lens

Not too heavy or large for telephoto range, great for bird photography, sharp and clean when there is enough light, focuses fast and reliably, well made and sturdy. Limitations become apparent on a cloudy or dark day when higher ISOs are required leading to increased image noise. There are brighter super telephoto lenses out there but are much much more expensive, much bigger and much heavier. The Olympus 100-400 is the best choice for advanced amateurs but professionals may need to put up with the weight, bulk and expense of brighter super telephoto lenses.

I had a Lumix G9 and the Panasonic Leica 100-400 lens, but wanted a newer body, so I sold the camera to a friend. For a while I used the Leica 100-400 with my new OM-1, then decided to sell the lens(same friend) and get this Olympus/OM System 100-400 and both the MC-14 and MC-20 teleconverters.The lens by itself is very sharp, and I'm 100% happy with the results. With the MC-14 you lose a stop of light, but I find that the sharpness is still really good, nearly the same as the bare lens. The MC-20 takes another stop of light, and also causes a visible loss of sharpness. I'm still happy with the images, but when you compare them to the other configurations you can see the difference.Attached pics: The Cooper's Hawk(90% sure that's the species) is shot with the MC-14, the Moon is shot with the MC-20

I bought this telephoto for my LUMIX G9, so I could have a lighter telephoto for my micro 4/3rds. And it doesn’t disappoint at all! The zoom on it and focus is pretty great in capturing amazing shots, as long as they aren’t moving. However, the focus speed with this lens and the camera I use is pretty slow, so you can’t capture that bird flying in the air. I’ve attached some images to show image quality, and for my purposes it does outstanding work! Overall, I think this is a great addition to your camera kit if you are looking for something to zoom in at 400 mm range using a micro 4/3rds.

I think this is a great lens for the price. This would be the next logical step up from a 45-150 kit lens for your micro 4/3 camera if you're into wildlife photography, or maybe you want to get some closeup portraits of animals.The pictures are sharp, it's not too bulky or heavy, and it has incredible reach. I typically use the MC-14 1.4x teleconvertor giving me 1120mm full frame equivalent focal length. The light weight coupled with the image stabilization means I have no problem shooting by hand at max zoom. Just mind your shutter speed.Image quality is very good. Better than I expected to be able to achieve, especially with the teleconvertor. It's not the sharpest lens in the world, but it's less than $1000 and plenty good enough for professional quality pictures. You just won't be making insane crops with this lens. You'll still want to get close even with the long reach. Light can be a problem. It is a very slow lens, so cloud cover will have you shooting high ISO. You won't be shooting owls at dusk. Luckily, I live in Arizona so light is very abundant.I think Micro 4/3 has a ton of advantages for wild life photographers looking to be more adventurous. The cameras are small and the crop factor gets you a ton of reach. I frequently hike with this lens. You don't need to haul around a giant tripod and gimbal. Some people are into finding a spot, setting up camp, and waiting for the action, but I much prefer to hike around and snap what I encounter. This is the lens for that. If you couple this lens with a used camera, you can really get into wildlife portrait photography for under two grand, which I don't think is that bad.Quality-wise, the lens feels durable and well made. It just feels like an expensive product in your hand. The zoom ring feels smooth, the switches feel high quality, and everything about it is functional. Weather sealing seems to have held up. I took it out in the rain on one trip and got caught in a downpour. I haven't had any issues. Overall, I'll highly recommend this lens to anyone looking to get into bird or wildlife photography.

Fantastic lens! Autofocus is fast with my Em5iii. Images are very sharp too in the correct light. Love it!

A bit too big for me and my copy rotates when mounted. No bueno