Zeiss created the new Loxia line specifically for Sony, adding high-quality manual focus primes to the growing list of native lenses for the Sony FE mount. With the Zeiss Loxia 35mm f/2 targeted for everyday use, the Loxia 50mm f/2 is a bit more specialized for such needs as portraiture, street, travel and landscape photography. Although Sony already had the excellent Sonnar T* FE 55mm f/1.8 from the beginning, the Loxia 50mm f/2 nicely fills the 50mm gap. And just like its 35mm f/2 counterpart, the Loxia 50mm f/2 is superb in its quality and build, designed to be similar to other traditional Zeiss lenses, with manual aperture control and a very compact size. This review is based on my 3 month shooting experience with both Loxia lenses on a variety of different Sony A7-series cameras.
The Zeiss Loxia 50mm f/2 is based on the 1896 Planar design by Dr. Paul Rudolph of Zeiss, one of the most successful and most plagiarized (according to Zeiss) lens designs in history. With a total of 6 lenses in 4 groups, the symmetric lens design of the lens is simpler than that of the Loxia 35mm f/2, which has 9 elements in 6 groups. Thanks to the relatively short flange distance of the Sony FE mount, the lens was made to be quite compact, measuring only 66.2mm in height, making it an ideal choice for Sony mirrorless cameras like the Sony A7 II. In this detailed review of the Zeiss Loxia 50mm f/2 lens, I will provide a thorough analysis of the lens, along with image samples and sharpness comparisons to the Sony Sonnar T* FE 55mm f/1.8.
1) Lens Specifications
- DeClick feature: For video applications, it is possible to ‘declick’ the aperture’s locking mechanism.
- Precise manual focus: Large rotation angle enables precise and smooth focusing.
- Virtually distortion-free optics: Elaborate optical design nearly eliminates distortion.
- High-grade full-metal casing: A precision-engineered full-metal casing, focus and aperture rings made of metal, and a tough front bayonet and filter screw make the lens incredibly durable.
- Full frame compatible: Optimized for film and sensors up to full 35 mm format (24 x 36 mm).
- Mount Type: Sony FE
- Focal Length (35mm format equivalent): 50mm
- Lens construction (elements/groups): 6/4
- Angle of view: 46.78°
- Number of diaphragm blades: 10
- Maximum aperture: f/2
- Minimum aperture: f/22
- Focus range: 0.45 m – ∞
- Weight (approx): 320g
- Dia. x length (approx): 66.2 x 62.1mm
- Filter size: 52mm
2) Lens Handling and Build
Zeiss has always proudly made lenses with superb build, and the Loxia 50mm f/2 is not an exception. With a full metal casing, metal aperture and focus rings, metal filter thread and mount, the lens feels like there is nothing but metal and glass inside. And indeed, it is certainly the case – nothing about the Loxia 50mm f/2 feels cheap and the lens is engineered to last for years. It feels like a solid chunk of high quality glass. Similar to modern Nikkor lenses, the Loxia 50mm f/2 also features a rubber gasket on the lens mount to prevent dust from getting into the camera chamber.
The focusing ring with an engraved distance scale is huge, making up most of the lens. It is very smooth to operate – when going from close focus distance of 0.45m to infinity, the front part of the lens extends a little bit, by approximately 5mm (focusing also moves the rear element of the lens). The focus ring has a hard stop at both close focus and infinity. Sadly, the infinity mark is not representative of true infinity focus – it is about 3mm away.
The aperture ring is also very smooth to operate and clicks in between 1/3 aperture stops. If one desires to have click-less operation of the aperture ring for videography needs, it is possible to use the provided wrench to remove this aperture locking by rotating a small screw on the rear mount of the lens (Zeiss refers to this as a “DeClick” feature). Right between the aperture ring and the blue rubber gasket, there is a thin ring that displays “Loxia 2/50 Ser. Num. Made in Japan”. Similar to other modern Zeiss lenses, the Loxia 50mm f/2 is made by Cosina in Japan.
Weighing 320 grams, the Zeiss 50mm f/2 is slightly lighter than the Loxia 35mm f/2, but about 40 grams heavier than the Sonnar T* FE 55mm f/1.8. And it should be, because it is a solid metal lens, while the Sonnar 55mm f/1.8 is partly metal and partly plastic, and does not have the same quality feel to it. Hence, the Loxia 50mm f/2 is designed to be small and lightweight for a compact mirrorless system. When mounted on Sony A7 cameras, it balances very nicely in hands. Just like the body of the lens, the hood is also made of metal. The inner part of the hood is covered with a thin layer of black cloth to reduce potential reflections into the lens and to absorb dust and other debris. The hood attaches and detaches easily and securely on the front part of the lens.
3) Manual Focus Operation
As I have stated a number of times before, Sony’s implementation of manual focus in its A7-series cameras is one of the best on the market. When you mount the Loxia 50mm f/2 and start turning the focus ring, the cameras immediately detect focus changes and automatically zoom in. This not only makes manual focus operation a breeze to use, but it also pretty much eliminates the potential for badly focused images. Unless your subject moves fast at a close distance and you are shooting wide open, you will always have perfectly focused images with this system. In comparison, the green dot indicator within a viewfinder of a DSLR (which uses phase detection focus operation) is prone to focus issues, since there is always too much “play”. You could slightly turn the focus point and get your subject blurry, while your camera still thinks that focus is good. This happens all the time, especially with fast prime lenses. With the instant zoom feature on mirrorless, you can see the subject very closely and you can really nail that focus every time, so whether you shoot wide open at f/2 or stopped down, you do not have to worry about focus precision issues.
4) Lens Sharpness, Contrast and Color Rendition
As I have already covered in my “best and worst Sony FE lenses for A7 cameras” article, the Zeiss Loxia 50mm f/2 delivers all around excellent performance when it comes to sharpness. It also beautifully renders colors and bokeh, thanks to its simple, yet very efficient optical design with a total of 6 elements in 4 groups. Here is an illustration showing the construction of the lens:
And as you can see, the classic Planar design indeed looks quite simplistic. However, it does not mean that the lens cannot deliver optically:
While the lens does not show record-breaking performance in the center like the Loxia 35mm f/2, its overall sharpness is much more balanced, thanks to pretty good mid-frame and corner performance. As you can see from the above graph, the lens starts out really strong already at f/2 and by f/4 reaches peak center performance. However, its mid-frame and the corners are worse in comparison, thanks to some field curvature exhibited by the lens at wide apertures. If you want the best overall performance throughout the image frame, the f/5.6-f/8 range will give you the best results. Focus shift is under control, which is always good news.
Overall, the Loxia 50mm f/2 is an excellent all-around performer when it comes to sharpness. To see how the Loxia 50mm f/2 compares to the Sony Sonnar T* FE 55m f/1.8, check out the Lens Comparisons section of this review.
Zeiss did not utilize any aspherical elements in the design of the lens, which is great, because aspherical lenses can actually result in onion rings in bokeh. On top of this, Zeiss utilized a unique diaphragm design, with a total of 10 straight blades, which render beautiful bokeh even when stopped down. I used the Loxia 50mm f/2 quite a bit for portraits and although the lens is a bit shorter than the Sonnar T* FE 55mm f/1.8 and has a smaller maximum aperture, I like its bokeh more in comparison. Why? The primary reason for this is aspheric lens elements in the Sonnar 55mm f/1.8 – they do result in onion-shaped bokeh, which is definitely distracting to look at, particularly when you have a close subject and distant highlights. The Loxia 50mm f/2 does not have this problem and its rendered highlights look very uniform and beautiful in comparison. But it is obviously a personal opinion – bokeh is very subjective and some people will disagree with me on this one. I provided a number of shots at f/2 in this review for you to look at and judge for yourself, whether you like the bokeh from the Loxia 50mm f/2 or not.
The Loxia 50mm f/2 shows some signs of vignetting at large apertures, particularly at infinity, but it is not distracting in any way. In fact, I really like how the lens naturally vignettes. None of the shots shown in this review have vignetting removed for that reason. Here is what Imatest measured against the FE 55mm f/1.8:
In comparison, the Sonnar T* FE 55mm f/1.8 has a significant amount of vignetting, which is actually not all that pleasing if not corrected. At close focus and equivalent aperture, the 55mm f/1.8 reaches an average of 2.28 stops darker corners and it gets even worse at infinity, reaching a whopping 3.05 stops. The vignetting on the Loxia 50mm f/2 looks very light in contrast.
Here is the worst case scenario at infinity focus:
Vignetting is distributed pretty evenly across the frame, with the darkest areas towards the edges of the frame.
7) Ghosting and Flare
Zeiss applied its anti-reflecting T* coating technologies on the Loxia 50mm f/2 to reduce ghosting and flare, so those should not be of big concern, even when including one or more bright sources of light in your frame. However, at 50mm, you will have a hard time producing shots with beautiful sunstars, unless the source of light is extremely small in the frame. Here is what a typical scene with the sun will look like at f/16:
As you can see, it is definitely not an ideal scenario. Another very important point to keep in mind, is that any lens that has an even number of diaphragm blades will produce that same amount in the sunstars. And since both Loxia 35mm f/2 and 50mm f/2 have 10 diaphragm blades, they will both produce exactly 10 bursts / lines in sunstars. If the number was odd, say 9 blades, then the sunstars would contain twice the number of bursts / lines.
Still, if you do want to include a bright source of light in your shots, it is nice to know that the Zeiss T* anti-reflective coating will be very helpful in not introducing ghosts and flares throughout the image.
Distortion is quite low on the Loxia 50mm f/2, although it is not as good as the Loxia 35mm f/2 (which practically has no distortion). Imatest measured barrel distortion at 0.97%, which is pretty low, but will be noticeable when photographing straight lines, especially at close distances. In comparison, the Sonnar T* FE 55mm f/1.8 measured a much lower barrel distortion of 0.27% (practically non-existent). If distortion bothers you, it is easy to fix in post-processing software like Lightroom or Photoshop. As of June of 2015, Lightroom and ACR already have lens profiles for the Loxia 50mm f/2, so you can apply distortion and vignetting corrections with a single click.
9) Chromatic Aberration
The Loxia 50mm f/2 handles chromatic aberration remarkably well. On average, Imatest measured about half a pixel of CA, which is very low:
In comparison, the Sonnar T* FE 55m f/1.8, sores even lower CA, showing remarkable performance.
Let’s move on to lens comparisons.
10) Zeiss Loxia 50mm f/2 vs Sony Sonnar T* FE 55mm f/1.8 Comparison
Let’s take a look at how the Zeiss Loxia 50mm f/2 compares to the Sony Sonnar T* FE 50mm f/1.8 lens:
We can see that both lenses have their strengths and weaknesses, but the Sonnar T* FE 55mm f/1.8 is clearly better optically. The Loxia 50mm f/2 achieves peak performance at f/4 with excellent center sharpness, but its mid-frame and corner performance are not in the same level as on the FE 55mm f/1.8, which performs remarkably well. The Sonnar design is clearly superior here, delivering outstanding sharpness throughout the frame. The FE 55mm f/1.8 practically has no field curvature and its sharpness is already superb at the maximum aperture.
If you are looking for the sharpness king, the Sonnar FE 55mm f/1.8 is clearly the way to go. But it is not all about sharpness is it? My personal preference lies with the Zeiss Loxia 50mm f/2, because it renders images more beautifully in my opinion, particularly when it comes to bokeh. The subject isolation on the 55mm f/1.8 will be slightly better, because you are shooting with a longer focal length and wider aperture, but images from the Loxia 50mm f/2 look more pleasing aesthetically to me. At the same time, the Loxia 50mm f/2 has no AF capabilities, so if you work in a fast-paced environment, the Sonnar FE 55mm f/1.8 will be a better overall choice. At the end of the day, both lenses deliver amazing results, so if you already own one, there is no need to worry about the other.
At this time, aside from the Samyang 50mm f/1.4 AS UMC and the Mitakon / Zhongyi 50mm f/0.95, there are no native lenses with a similar focal length for the Sony FE mount, so I cannot yet provide other comparisons. Once more lenses become available and I get a chance to test the above-mentioned lenses, I will be testing those and updating this review accordingly.
The Loxia 50mm f/2 is yet another great addition to the growing family of native lenses for the Sony FE mount. Although it is a manual-focus lens, the ability to instantly zoom in on the Sony A7-series cameras makes the Loxia 50mm f/2 a breeze to use for pretty much any kind of photography. Thanks to the tight collaboration of Zeiss and Sony, gaps are getting filled quickly and the list of dependable lenses is growing very fast. With the two Loxia lenses and the newly announced Batis lenses, Zeiss is clearly putting a lot of bets on Sony’s mirrorless cameras, so it looks like both companies are anticipating tremendous growth in the coming years. And they should, because they are doing everything they can to bring innovative and groundbreaking products to the market. Sony’s much anticipated A7R II looks extremely promising and if the company puts enough resources on more high-quality lenses to compete with DSLRs, it will get harder for Nikon and Canon to compete.
I have been enjoying both Loxia lenses ever since I got a hold of them a few months ago. When coupled with the Sony A7-series camera bodies, the two lenses felt at home, thanks to their sturdy construction and superb handling. I took both the 35mm f/2 and the 50mm f/2 with me to Jordan and Sri Lanka trips and I found myself using those two over Sony lenses pretty much all the time. If I did not have to test Sony lenses, they would stay glued to the cameras. The Loxia 50mm f/2 might have a simplistic optical design when compared to other 50mm primes, but the lens has superb colors, beautiful bokeh and amazing sharpness – what more could one ask for from a lens?
At $950, the Loxia 50mm f/2 is not a cheap lens, particularly when compared to the faster and AF-capable Sonnar T* FE 55mm f/1.8 ZA, which sells for $50 more. It is a tough lens to compete with, thanks to its stellar sharpness and all-around performance, as shown earlier in this review. At the same time, Zeiss does not always put sharpness as the ultimate goal of every lens design – many of the classic lenses are optimized for beautiful rendering and colors first, sharpness second. The same goes for the Loxia 50mm f/2 – it is not a razor sharp Otus and it is not meant to be one. The reasons for choosing the Loxia 50mm f/2 over the Sonnar T* FE 55mm f/1.8 ZA are: superior build quality and ergonomics, more compact design, better colors and bokeh (subjective) and rendering of images (also subjective). For these reasons, I personally prefer the Loxia to the Sonnar.
And this sounds silly, because both lenses have the Zeiss label on them! You might be wondering about the differences between the two and who designed and made them. “ZA” lenses with the Sony name in them are either designed by Zeiss, or designed by ex-Minolta engineers at Sony and later approved by Zeiss. The manufacturing process is fully controlled by Sony corporation, which often sub-contracts the manufacturing process to other companies in Japan and other parts of Asia (mainly China and Thailand). In contrast, Zeiss-labeled lenses like the Loxia 50mm f/2 are 100% designed by Zeiss engineers and the actual production is sub-contracted to companies like Cosina in Japan (Zeiss ceased most of its lens production in Germany a while ago). Zeiss fully controls and oversees the manufacturing process, ensuring that every lens made strictly adheres to the strict QA and testing standards established by Zeiss Germany. The reason why Zeiss continues to make manual focus lenses, is because it does not have to license and pay royalty fees to the owner of the mount (which in this case is Sony). So keep this in mind when looking at Sony lenses with a Zeiss label – those might have little to do with the Zeiss name in reality…
Overall, I really enjoyed shooting with the Zeiss Loxia 50mm f/2 lens and I would certainly recommend it to anyone who is looking for a high-quality standard prime for the Sony FE mount. I cannot wait to see Zeiss produce more of these high-quality lenses for the Sony mount!
12) Where to Buy
B&H is currently selling the Zeiss Loxia 50mm f/2 lens for $949 (as of 06/16/2015).
13) More image samples
All Images Copyright © Nasim Mansurov, All Rights Reserved. Copying or reproduction is not permitted without written permission from the author.
Zeiss Loxia 50mm f/2
- Optical Performance
- Bokeh Quality
- Build Quality
- Focus Speed and Accuracy
- Size and Weight
Photography Life Overall Rating