Introduction
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH (H-X2550) is a brand new quick telephoto zoom lens for the Micro 4 Thirds digicam system. It’s the world’s first telephoto zoom lens to supply a most aperture of f/1.7 all through its vary.
That includes silent, high-speed focusing due to a 240fps high-speed inside focus drive system, the mud/splash/freeze-resistant Panasonic 25-50mm lens provides a flexible focal vary of 50-100mm in 35mm phrases.
Optically it is comprised of 16 parts in 11 teams, together with one aspherical lens, three ED (Further-low Dispersion) lenses and one UHR (extremely excessive refractive) lens, and has 9 diaphragm blades which assist give the aperture a rounded form.
The Leica DG 25-50mm has a de-clicked aperture ring for simpler video recording, and there is additionally a conventional focus clutch mechanism which allows prompt AF/MF switching and correct handbook focusing.
This lens has been designed to completely match the Leica DG Vario-Summilux 10-25mm F1.7 ASPH lens, with the pair successfully functioning as eight conventional fastened focal size lenses (20mm / 24mm / 28mm / 35mm / 50mm / 75mm / 85mm / 100mm) while providing the identical or a good increased stage of high quality.
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH lens is priced at £1,799.99 / $1,799.99 within the UK and the US, respectively.
Ease of Use
Given the quick most aperture of f/1.7 on supply all through the zoom vary, the Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH is unsurprisingly giant and heavy for a Micro 4 Thirds lens, measuring 127.6mm / 5.02inch in size and weighing 654g / 1.44lb, which is about the identical dimension and weight because the 10-25mm F1.7 lens.
Not like the 10-25mm lens, although, zooming is inside, so the lens barrel does not extends when zooming out from 25mm to the 50mm focal size.
The lens has a spotlight clutch mechanism quite than an AF/M change for selecting the focusing mode.
When the focusing ring is pushed ahead, the lens is locked into autofocus mode.
When the focusing ring is pulled again, the focusing distance scale with depth-of-field markings is revealed and you’ll manually focus with the lens – very neat.
Word that it is a focus-by-wire lens which makes use of a stepping motor. There are onerous stops at each ends of the 0.28m/0.92ft to infinity focusing vary, however no depth of subject scale on the barrel.
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH lens provides silent focusing, making it excellent for video recording. In use, we discovered the AF system to be very fast, correct and dependable on the flagship Panasonic GH5 II digicam.
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH has a conventional aperture ring on the lens barrel, which lets you set the aperture in 1/3 steps, full with aperture markings on the lens barrel. The aperture can also be proven within the viewfinder or on the LCD display screen as you modify it.
The quite skinny aperture ring toggles between auto aperture management (the ring is about to A) or handbook aperture management (the ring is about to one of many aperture values).
The aperture ring proved to be properly damped in use, though as a result of the ring is declicked, the lens is healthier fitted to video use than for stills, because it’s tough to set the aperture precisely to one of many 1/third values with out having to double-check it first by way of the viewfinder or rear LCD display screen.
The 77mm filter thread doesn’t rotate on focus, which is nice information for customers of polarisers and graduated impartial density filters.
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH has a lens mount is, fortunately, made from steel. The lens additionally boasts a mud and splash-proof design and is even freeze-proof right down to -10C, though Panasonic stops in need of calling it totally weatherproof.
Usefully the lens comes with an excellent high quality spherical lens hood with a button to lock it into place and launch it. Panasonic additionally embody a material storage bag within the field.
Focal Vary
On the 25mm finish of the zoom vary, the lens has a diagonal angle of view of 47°, equal to that of a 50mm lens in a 35mm system.
25mm
On the 25mm finish, the angle of view is 24°, which is identical as that of a 100mm lens on a 35mm full-frame digicam.
50mm
Chromatic Aberrations
Chromatic aberrations, sometimes seen as purple or blue fringes alongside contrasty edges, are usually not an issue with the Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH lens.
25mm
50mm
Distortion
There may be nearly no distortion seen at both finish of the zoom vary.
25mm
50mm
Mild Fall-off
With the Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH lens set to its most aperture of f/1.7, you possibly can see some mild fall-off within the corners, however nothing too extreme.
25mm
50mm
Macro
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH lens has a most 0.21x magnification ranking and is ready to focus at 0.28m / 0.92ft away from the topic on the 25mm focal size and 0.31m/1.02ft on the 50mm focal size.
Sunstars and Flare
The Panasonic Leica DG Vario-Summilux 25-50mm F1.7 ASPH produces very good sunstars when stopped-down to f/16, as proven beneath.
The lens is kind of prone to flare when taking pictures straight into the solar, although, even with the lens hood fitted.
Bokeh
Bokeh is a phrase used for the out-of-focus areas of {a photograph}, and is normally described in qualitative phrases, reminiscent of clean / creamy / harsh and so forth.
Within the Leica DG Vario-Summilux 25-50mm F1.7 ASPH lens, Panasonic have employed a diaphragm with 9 rounded blades, which has resulted in very good bokeh, a minimum of in our opinion.
Nevertheless, recognising that bokeh analysis is subjective, we’ve got supplied a number of examples on your perusal.
Sharpness
As a way to present you ways sharp this lens is, we’re offering 100% crops on the next pages.
