Pair it with the Olympus OM-D E-M1X and you also get the benefit of Sync IS (which employs the in-body and in-lens stabilization in tandem) that gives you 5 stops of image stabilization – meaning that you can shoot without a tripod.A 1200mm lens you can use handheld? That alone is worth the price of admission. I've now had the 300mm F4 Pro for a little over 3 months. The main development has been that I've upgraded to the Olympus E-M1 MKII as the auto... To benefit from the dual IS you need to pair it with an Olympus body, other makes are not compatible meaning you have to select lens or camera IS

If 300mm is simply not enough reach, the Olympus MC-14 and Olympus MC-20 are both compatible with the Olympus 300mm f/4.0 IS PRO. These teleconverters multiply the focal length by a factor of 1.4 and 2 respectively. This kind of no-nonsense functionality usually makes teleconverters a bit boring to write about. However, when it comes to Micro Four Thirds (MFT), teleconverters suddenly become a whole lot more exciting. The teleconverter doubles the focal length of the master lens, which in the case of the 150-400mm results in an astonishing reach of 2000mm (working in tandem with the lens' integrated 1.25x teleconverter). You’re right in the sense that a 300mm f/4 lens will always be 300mm f/4, regardless of the sensor behind it – but the concept of a crop factor is still useful in practical terms. Nicholas is right that it applies to both focal length and aperture. (It also applies to ISO, but with a [crop factor The lens was so sharp, I even found moire on birds feathers, an issue I’d never encountered before! DC-G9 + OLYMPUS M.300mm f/4 @ 300mm, ISO 800, 1/500, f/4.0 BokehThe Olympus 300mm f/4.0 IS PRO is a prime lens fixed at 300mm. There are longer options available for Micro Four Thirds that reach up to 400mm. However, the Olympus 300mm f/4.0 IS PRO is so sharp and high performing it feels like it is over 300mm, simply because the increased sharpness allows more cropping compared to the Olympus 100-300mm f/4-5.6 that I previously used.

This first shot of a swift in flight I'm particularly pleased with and for me confirms that the Olympus MFT set up can now compete with Canon and Nikon for shooting wildlife.The only handling flaw I noticed in my time with this lens involves the focus ring. The ring rotates very smoothly, but the lens easily switches from autofocus to manual-only by sliding the focus ring into the manual position. However, keep in mind that crop factors also apply to aperture; so, using this lens is akin to using a 600mm f/8 on full-frame.’