OLYMPUS 300MM F/4.0 IS PRO ED M.ZUIKO
If you want to do serious nature photography with an SLR camera, then you soon end up with a lens with a 600mm focal length. And a sturdy tripod and a cart for hauling around the tripod and telephoto lens. Photographing by hand with 600mm is really not an option.
It is with the Olympus 300mm f/4.
Thanks to the crop factor of the micro-43 sensor, the field of view of this 300mm lens is equal to the field of view of a 600mm lens on an SLR camera with a full-frame sensor. Thanks to the shorter focal length, you benefit from a larger focal depth. The high brightness of f/4 is unchanged, so that you have a short shutter time even in low light. The image quality is very high starting at full aperture. And the image stabilization is super. That combination means that you can often use a low ISO value with this lens, so that the eventual image quality (signal-to-noise ratio, dynamic range and resolution) comes very close to that of the much more expensive and larger telephoto lenses on SLR cameras. And if you don’t think 300mm is long enough, then you can combine this lens with the Olympus 1.4x converter, while retaining AF.