The Leica DG Vario-Elmar 100-400mm f/4-6.3 ASPH. POWER O.I.S. Lens from Panasonic offers a truly expansive 200-800mm equivalent focal length range, yet retains a relatively compact stature to suit the Micro Four Thirds system. Characterized by its Leica branding, this sophisticated optic employs aspherical and extra-low dispersion elements to significantly reduce chromatic and spherical aberrations throughout the zoom range for a high degree of image clarity and sharpness. Benefitting both stills shooting and video recording, a 240 fps high-speed AF motor is both quiet and precise, and a focus limiter function can be employed to constrain the focusing range for even quicker performance. Additionally, the physical design of the lens utilizes a gapless construction that renders it both dust- and moisture-resistant for use in inclement conditions. And while its lightweight, compact form factor is suitable for handheld shooting, the 100-400mm f/4-6.3 also features a removable rotating tripod collar for fast switching between horizontal and vertical shooting orientations when working atop a monopod or tripod. Designed in collaboration with Leica, the 20 elements, 13 groups optical design incorporates one aspherical extra-low dispersion element, one Ultra Extra-Low Dispersion element, and two extra-low dispersion elements.  POWER O.I.S. mechanism helps to control camera shake for sharper handheld shooting. This system is also compatible with the Dual I.S. function in select Lumix G cameras, which more effectively minimizes the appearance of camera shake by using both sensor-shift and lens-shift type stabilization methods. Focus Limiter allows you to constrain the focusing range of the lens from its minimum focusing distance to infinity, or from 16.4' to infinity. A rounded nine-blade diaphragm contributes to a pleasing bokeh quality when working with selective focus and shallow depth of field techniques. A quick-shift, two-part rotating tripod collar permits quick switching between horizontal and vertical shooting orientations, and keeps the lens controls in the same place once rotated for more intuitive handling. A zoom ring lock prevents unwanted lens creep from occurring while carrying the lens.