Amateur Photographer verdict
Excellent value for money, particularly if you’re looking for a portrait-friendly lens with modern features, good optics and a clever filter system- Very good image quality wide open
- Compact and lightweight for an f/1.4
- Magnetic filters and cap support
- AF slightly slow for fast action
- Aperture ring lacks a lock
At a glance:
- Price: $599 / £639
- Filter Diameter: 72mm
- Length: 99mm (133mm with hood)
- Weight: 580g (610g with hood)
- Lens Mount: Sony E (FE)
How we test lenses
We test lenses by using them to take photographs and video in a wide range of real-world situations. We test every lens for all aspects of image quality: sharpness, contrast, background blur and bokeh. We evaluate their balance, handling and physical controls, checking the usability of zoom rings and focus rings. Also testing their autofocus across a range of different subjects and shooting scenarios and assess the built-in stabilisation systems if present.
The Kase 85mm F1.4 Auto Focus is a fast short telephoto prime lens designed for full-frame mirrorless cameras and aimed at portrait photographers, videographers and enthusiasts who appreciate shallow depth of field effects. With a maximum aperture of f/1.4, it’s ideal for low-light conditions and creating strong subject separation with background blur.
It’s currently available with the Sony FE and Nikon Z mounts, and a Fujifilm X version is expected soon. On APS-C format cameras, it has an effective focal length of around 127.5mm, which puts it well within classic portrait territory. It costs $599 / £639, which is great value for a lens of this spec – except the Viltrox AF 85mm F1.4 Pro is even cheaper.
Kase 85mm F1.4 AF – Features
Inside, the lens has an optical construction comprising 13 elements arranged in 10 groups, including five low-dispersion elements and two made from high-refractive-index glass. This helps to reduce chromatic aberration and distortion while enhancing clarity and contrast. There’s also a 13-blade diaphragm, which is rather generous, and is intended to deliver smooth, rounded bokeh that should keep background highlights soft and pleasing.
Kase has used a stepping motor (STM) to power the autofocus system. These motors are generally fast, near-silent and smooth in operation, which makes them useful not just for stills but also video work. There are two function buttons on the lens barrel – Fn1 and Fn2 – that can be customised depending on what your camera allows. Fn2 is especially handy as a focus memory button: a short press can return the lens to its minimum focusing distance, or with a longer press, locks it to your current focus point for easy recall later.
You also get a manual aperture ring with clearly defined click stops – which can be de-clicked if you prefer smooth transitions for video – and there’s an ‘A’ position to switch control back to the camera body. However, there’s no lock on the ring, and it’s all too easy to slide past f/16 into ‘A’ or vice versa, particularly if you’re shooting with the ring de-clicked. It’s something I found myself checking more than once during a shoot.
Then there’s the Kase Magnetic Inlaid Ring. This simple-looking accessory is one of the most useful features of the whole package. That said, it’s available to buy separate for around £20-£24 depending on the size you need. It allows magnetic filters to be snapped on and off in seconds – and crucially, without needing to remove the lens hood. It also supports the included magnetic lens cap, which is a nice addition. It attaches firmly, removes without a fight, and generally makes life that bit easier.
The lens also has a USB-C port on the mount ring for easy firmware updates. This is something I first saw on a Viltrox lens and I’d like to see rolled out more widely.
Kase 85mm F1.4 AF – Build and Handling
At 82mm in diameter and 99mm in length, the Kase 85mm F1.4 Auto Focus lens is compact for its class. It weighs in at 580g without the hood, which is around 220g lighter than the Viltrox AF 85mm F1.4 Pro FE I reviewed recently. That difference is enough to be noticeable, especially towards the end of a long day if you’re working hand-held.
Overall, the build quality feels very good. The barrel combines aluminium alloy and polycarbonate, and there’s a gasket around the mount for some degree of weather resistance. The focus ring is broad and rotates smoothly, with enough resistance to feel precise but not stiff. The aperture ring is nicely damped but – as mentioned earlier – the lack of a lock is a shame. However, it’s good to see a click/de-click switch for the aperture ring. With the clicks engaged, you get feedback with every 1/3 stop adjustment to aperture setting. It’s handy when you’re looking through the viewfinder and concentrating on your subject rather than looking at the settings display.
The two function buttons are positioned on the left of the lens barrel and fall under the thumb naturally when shooting. I found myself using the minimum focus feature quite often, particularly when out and about. Once you start using it, you find yourself reaching for it more often.
The speedy customisation of the Fn2 button is also helpful if you’re waiting for a subject to appear. It means you can get ready quickly and reduce the amount of hunting. The lens retains your custom focus distance if you turn the camera off and on again, but removing the battery or unmounting the lens resets it. That’s arguably a mixed blessing and something to be aware of if you’re relying on it for a specific setup.
Kase 85mm F1.4 AF – Autofocus
Autofocusing with the Kase 85mm F1.4 Auto Focus lens is generally pretty quick and decisive. It works well with the Eye Detection AF on Sony cameras and manages to lock on accurately even in relatively low light. The STM motor is also quiet enough for video use, and I didn’t pick up any distracting motor noise while shooting.
That said, it’s not the fastest lens I’ve tested when it comes to tracking moving subjects. For example, when I tried grabbing a few candid shots of a fast-moving group on the street, the Viltrox 85mm f/1.4 edged ahead in terms of speed and accuracy. But for portraits, headshots or studio work, which is likely this lens’s main application, I find the Kase’s autofocus to be entirely fit for purpose.
There’s also significant focus breathing which means the lens appears to zoom as the focus is shifted from the closest point to infinity. That may not be a problem for most stills portraiture, but it could be an issue for video as a subject moves towards or away from the camera.
Kase 85mm F1.4 AF – Image Quality
The Kase 85mm F1.4 Auto Focus lens puts in a very respectable performance with regards to image quality, especially considering its price. It’s already sharp in the centre at f/1.4, and it sharpens up nicely by f/4. The very best results come between f/5.6 and f/8, where sharpness is excellent from corner to corner.
There’s some expected fall-off towards the corners at f/1.4, but it’s not distracting in most real shooting situations and quickly improves as you stop down. Vignetting is visible at the wider aperture settings up to around f/5.6, though it can add a bit of mood to portraits. By f/8 it’s gone.
There’s a touch of pincushion distortion, which isn’t unusual for a lens like this, and it shouldn’t pose a problem unless you’re super-critical and photographing architecture or something with lots of perfectly straight lines at the edges of the frame. Similarly, chromatic aberration is well controlled – I noticed only minor fringing along the odd high-contrast edge, which disappeared with a quick click in Adobe Camera Raw.
The bokeh is another strength. Background blur looks smooth and natural, and out-of-focus highlights are generally clean. However, you are likely to see highlights with a slightly angular shape, reflecting the form of the aperture blades. And those near the edges of the frame can take on a rugby-ball shape, which is fairly typical and not something I find especially distracting.
Flare is well-controlled thanks to the deep lens hood, but without the hood, you may see more dramatic rainbow artefacts and hotspots when sunlight skuds across the front element. This makes the ability to use Kase magnetic filters with the hood all the more attractive.
Kase 85mm F1.4 AF – Verdict
The Kase 85mm F1.4 Auto Focus lens surprised me. Not just because of the image quality – which is very good indeed – but also because of the little practical touches that make it nice to use day-to-day. The magnetic filter ring system is a genuinely useful addition, particularly if you often work with ND or polarising filters. I’d love to see more manufacturers adopting something similar, although you can of course purchase an adapter separately for a modest outlay.
The lens’s autofocus is suitably quiet and accurate for portraits, and while it may not be the fastest option for action or street photography, it’s more than good enough for its target audience. And the weight saving compared to some rivals is very welcome when you’re working handheld for any length of time.
It’s not without its quirks, though. The aperture ring could do with a lock to prevent accidental shifts, and some may like to see the focus memory setting retained after a lens change. But these are relatively minor annoyances, not deal-breakers.
For £639, the Kase 85mm F1.4 offers excellent value for money, particularly if you’re looking for a portrait-friendly lens with modern features, good optics and a clever filter system. It might not have the brand recognition of the bigger names, but it certainly holds its own in terms of performance. In some way, the Viltrox AF 85mm F1.4 Pro FE has the edge, but on the other hand, the two function buttons on the Kase lens are handy.
Full specifications
| Filter Diameter | 72mm |
| Lens Elements | 13 |
| Groups | 10 |
| Diaphragm blades | 13 |
| Aperture | f/1.4-16 |
| Min. focus | 0.7m |
| Length | 99mm (133mm with hood) |
| Diameter | 82mm |
| Weight | 580g (610g with hood) |
| Lens Mount | Sony E (FE) |
| Included accessories | Magnetic front cap, rear cap, lens hood, soft case |
