Test of Panasonic Lumix G Vario 100-300mm with Olympus E-M1III

Panasonic Lumix G Vario 100-300mm F4.0-5.6 ASPH is a very versatile Micro 4/3 telephoto lens in a surprisingly small and light package. Mine is the original version, not the newer Mark II type, and is a few years old by now. Most of my other lenses are Olympus M.Zuiko because I shoot Olympus bodies (E-M5II and E-M1III), and I am spoiled by how well the cameras work in tandem with Olympus lenses to deliver an amazing level of image stabilization (IS).  The Panasonic lens, however, is a slightly different story because it its own built-in optical image stabilization (OIS) seems to deliver substandard results compared to the in-body-only IS of my Olympus cameras. 

Below is the latest of the several tests I recently ran with this Panasonic Lumix G Vario 100-300 coupled with my E-M1III in the lens IS priority mode, with and without the lens OIS activated. Both photos are crops of the original frames each of which was selected as the sharpest among the several frames of the same type.

Both were shot as follows:

• 275 mm (because the lens is sharp enough up to 280mm and goes softer above that)
• speed 1/80 sec (the fading evening light didn't allow for a faster speed without raising ISO)
• aperture F/8 (which seems to be "the sweet spot" for the maximum sharpness of this lens)
• ISO 400
• handheld while sitting down and holding the lens by the hood to minimize shake.

Lens OIS is on (camera's IS is off due to the lens priority mode)

Lens OIS is off (camera's IS is on)

The above images clearly show that even when the lens is almost fully extended the E-M1III's IS delivers a visibly crisper and sharper image than does the lens's OIS.  And these aren't flukes because I have obtained very similar results with several other subjects and at different focal lengths, exposures and apertures.

Another problem that I often noticed in shots made with the 100-300's OIS enabled are geometric distortions between successive frames shot in the burst mode. They manifest themselves as a widening or narrowing of objects (or portions thereof) from one frame to the next as well as floating spots of localized blurriness that appear in random areas of the field of vision. With the lens' OIS turned off such artifacts aren't visible.