… with the Panasonic Leica DG Vario-Elmarit 8-18mm f2.8-4 micro four thirds lens which will be referred to hence forth as the 8-18 for brevity’s sake. For those who prefer video there is a video review at the bottom of the page.
The 8-18 was introduced as part of Panasonic’s Leica branded f2.8-4 lens range in April 2017. I was immediately interested as I wanted a wide-angle zoom in m4/3. I had discounted the existing Panasonic 7-14mm f4 and the Olympus 7-14mm f2.8 because they wouldn’t accept screw in filters and the Olympus 9-18mm f4-5.6 because the collapsible design means the lens is prone to failure due to the internal ribbon cables breaking. The new 8-18 presented itself with a high quality metal construction that was splash proof and a modest 67mm filter thread. I wanted to use the lens for video work and so the ability to take a variable neutral density filter was a must. So when the lens became available here in Australia I plonked my cash down and got one.
My first impression on opening the box was that it is a quality bit of kit – it feels nice in the hand with a cool metallic feel and satisfying density. The bulbous front element is well recessed and combined with the excellent locking lens hood means that it is protected from stray light and from being physically damaged. The lens barrel has two ring controls – the front being for focus and the rear for zoom – and a switch for selecting auto or manual focus.The focusing ring is of the fly-by-wire type that twiddles endlessly – I wish that Panasonic would follow Olympus’s lead and have the pull back clutch type focusing rings with hard stops. The zoom ring is nicely damped and travels in a smooth 90º rotation. Another gripe is that both Panasonic and Olympus are members of the m4/3 consortium so why oh why can’t they agree on which way the zoom ring turns? Both zoom and focus are internal which is nice as it does not affect the centre of balance while using a gimbal. The lens body is finished in a smooth black satin with the engravings done in the Leica font and colours. The lens mount is metal and looks to be chrome plated brass. So full marks to Panasonic for presentation.
|focal length||8-18mm (16-36mm 35mm full frame equivalent)|
|angle of view||62º – 107º|
|minimum focusing distance||23cm|
|maximum magnification||0.12 x|
|number of lens elements||15|
|number of lens groups||10|
The lens construction is 15 elements in 10 groups with 1 aspherical extra low dispersion element, 2 extra low dispersion elements and 1 ultra high refractive index element. Combined with the nano coatings they should reduce internal flare, distortion and chromatic aberration. Control of distortion and chromatic aberration is also aided by an internal software profile that is baked into the image file. A lot of people don’t like this approach as they feel corrections should be made optically. The main criticism is that there is too much of an image quality hit in the corners with this approach. Hasselblad was the manufacturer to take this approach with their H3 camera and when that was introduced there were few complaints about image quality. The reality is that using lens profiles means lenses can be cheaper, smaller, and lighter than their optically optimised brethren.
The 8-18 has a variable aperture and unfortunately it quickly steps down as you zoom in as can be seen by the chart below.
I’ve done my standard tests to look for distortion, chromatic aberration, and sharpness at 8mm, 12mm and 18mm to give an indication of how the lens does throughout its zoom range. I have just for interest sake posted images with no profile correction to give an idea of what the lens is actually doing. Click on the images to see them at full size.
At 8mm without any inbuilt lens profile applied there is very obvious barrel distortion and vignetting at f2.8. With the profile applied there is still a very slight barrel distortion and the vignetting remains until f5.6. In terms of sharpness well at f2.8 the centre of the image is nicely sharp and contrasty and remain so until f16 when diffraction kicks in and softens the image. In the corners the story is different, at f2.8 the corners are significantly softer and less contrasty than the centre, they improve a little as you stop down reaching best performance at f5.6 and then get worse at f16 with diffraction. A small amount of chromatic aberration is present throughout the aperture range and is easily corrected in post.
At 12mm we can see no distortion when the lens profile is applied and the vignetting is about 1/2 stop and is barely discernible. Wide open at f3.4 the centre of the image is sharp and contrasty and the best performance is at f5.6. In the corners the image is softer and has less contrast than the centre. The best performance is at f8. Diffraction starts to set in at f11.
At 18mm there is some pincushion distortion in the profile corrected image. There is also a tiny bit of vignetting at f4 but this clears up at f5.6. Sharpness at f4 is very, very good in the centre throughout the aperture range only deteriorating at f16 due to diffraction.The corners are remarkably sharp at f4 but have slightly less contrast than the centre. Peak performance sets in at f5.6 and then again diffraction rears its ugly head at f16 and spoils the party. Chromatic aberration is very well controlled across the whole range and is very, very slight.
Like most wide-angle zooms the 8-18 is prone to flare. In order to reduce this the engineers recessed the front lens element and then provided a decent lens hood. The Panasonic 7-14mm f4 caused purple blobs on Olympus cameras when there was a specular light source in the frame. Some people pointed the finger at the difference in UV coatings between Panasonic and Olympus cameras. Others said the thickness of the Olympus sensor stack caused the problem. Anyway the 8-18 is thankfully free of those artefacts. Shooting into the sun there is some veiling flare and ghosting.
Auto focus is done via a stepping motor and it is designed to work with Panasonic’s Depth From Defocus technology that is basically a contrast based auto focus system that is enhanced by software profiles for each Panasonic lens. Single point autofocus in single shot drive mode is incredibly fast and accurate. I decided to check the Continuous Auto Focus by continuous shooting at medium speed wide open on the Panasonic G85 with a person walking slowly towards the camera at focal lengths of 8mm and 18mm. All the shots were in focus. Then I tried to see how the lens would perform on a camera without DFD – in this case an Olympus OMD EM1 mk i. At 8mm and f2.8 all the images were in focus. At 18mm shooting a burst of 10 images the camera lost focus on the last 2 images of the burst. So this very limited test shows that the autofocus of the lens does perform better on Panasonic cameras with DFD.
Ok I’ve had the lens a year now and I’ve used it for stills, time lapses and video shooting on the afore-mentioned EM1 and G85 along with an EP5 and EM10 so what can I say. The in camera lens profiles make a huge difference in terms of distortion, but most people won’t see this as they’ll see the corrected images. I did expect this to have some impact on sharpness in the corners but was pleasantly surprised to find that not the case at all. Most zooms perform best at the short end and become softer at the long end. With my copy of the 8-18 this lens is very good at the long end and it is a little softer at the short end. The ability to use filters is a boon for landscape photography and video. The 67mm filter size does not make filter purchases onerous and with the wide-angle filter holder you can use the Cokin P filter system with rectangular filter with an 85mm width. It is really nice not to use filters the size of dinner plates with this lens. I’ve been caught in a couple of downpours while using the 8-18 and have had no problems. I have found the lens immensely satisfying to use and have put it to more uses than I originally thought I would. In all I feel it is a very good lens if you can live without a fixed aperture. I would definitely recommend it.