Panasonic Leica DG Vario-Summilux 10-25mm f/1.7 ASPH technical details

Leica Vario-Summilux 10-25mm f1.7

The new Vario-Summilux 10-25mm f/1.7 is Panasonic’s eleventh Leica DG lens and the first constant maximum aperture zoom released for the G series in a while. With its wide range of useful focal length combined with that super-fast maximum aperture it’s set to become a firm favourite with both stills and video photographers. The lens has a range of viewing angles the equivalent of a 20-50mm lens on a full frame camera, and neatly covers off the popular 20mm, 21mm, 24mm, 28mm, 35mm, 43mm and 50mm focal lengths offered in fixed focal length lens systems – all at the super-fast maximum aperture of f/1.7.


Also super-fast is the focusing system. The lens runs at 240fps, and so offers lightning quick reactions capable of keeping up with the Lumix G9. The reactive frame rate means AF starts more quickly and that movements in the subject will be detected more readily to help speedy AF tracking. Thanks to an inner focusing system the lens is silent in use.

When you need manual focus it is available in an instant, as simply pulling back the focusing ring deactivates AF and switches the lens to manual operation. Helpfully, pulling back the ring exposes distance markings in feet and metres to help pre-focus and to predict next focus positions.

Construction and resolution

The lens is constructed using 17 elements in 12 groups, and includes 3 aspherical elements, 4 extra-low dispersion lenses and 1 ultra-high refractive index element. These special elements help to keep the lens as sharp as possible right across the frame even when it is used at the widest aperture. Four ED elements should ensure the lens doesn’t produce the colour errors that reduce image sharpness and create coloured fringing around the subject in high contrast scenes.

Panasonic has also been careful to ensure that focus breathing (when the background changes shape during focusing adjustments) is minimised to avoid distractions during filming. The smooth zoom ring will help videographers keep the camera still during focal length changes too, and the way the internal elements are arranged there is no loss of balance when shifting from one extreme of the zoom to the other.

Smooth aperture action

Leica Vario-Summilux 10-25mm f1.7

To ensure beautifully round out-of-focus highlights at that wide aperture the lens is fitted with a nine-bladed iris that produces a smooth circular opening. What’s more, with the click-less aperture ring moving from one f/stop to the next exposure changes can be managed gradually and seamlessly. Still marked with third-stop increments, the aperture ring turns without clicking into place at the stop settings, which allows videographers to adjust apertures during filming without the sound of the clicks interrupting the audio track. It also means that aperture adjustments can be made gradually and be more easily disguised in the footage than when using a clicked aperture ring that only allows 1/3rd-stop leaps that will be clearly visible in the movie.

The only click on the ring is where the A(uto) marker is, which allows photographers to use body controls to alter apertures instead of the aperture ring itself.

Resisting the elements

This is a very well made lens that is designed for hard use and to last a long time. The outer barrel and rings are all made from metal and finished with metal surfaces, while the whole unit is resistant to the ingress of dust and moisture. Panasonic says the lens will be able to operate in temperatures as low as -10°C.

The lens measures 128mm in length, has a maximum diameter of 87.6mm, and weighs 690g.

The Panasonic Leica DG Vario-Summilux 10-25mm f/1.7 ASPH will be available from the 15th July for £1799.99



Focal Length 10-25mm
Aperture F/1.7-16
Optical Construction 17 elements in 12 groups
Special elements 3 ASPH, 4 ED, 1UHR
Diaphram 9 blades
Closest focus 0.28m
Max magnification 0.14x
Filter thread 77mm
Max diameter 87.6mm
Length 128mm
Weight 690g


Follow these links to read:

The Panasonic Leica DG Vario-Summilux 10-25mm f/1.7 press release

Our Panasonic Leica DG Vario-Summilux 10-25mm f/1.7 hands-on gallery and videos

To discuss this fabulous lens head to our Lumix Lens Forum

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