I must be getting rusty. As the time comes to write a review of the Zeiss Loxia 25 that co-author Philippe so kindly lent me for a 2-week trip to Japan, words fail me. The thing is, there isn’t a lot to say about this lens, if you stick to the conventional review process. It isn’t a lens you can dissect into technical aspects to get a good feel of its use, performance or significance. I’d rather take a different route here.
To me, the Loxia 25 is a brave attempt by Zeiss to make the photo world a better one. The hopeful cynic in me rather thinks that Zeiss are serving a niche that must be juicy enough to justify the effort. And the romantic in me finds that very reassuring, in a hobby so heavily dominated by technical specification and performance at the expense of beauty.
That I have so little to say about the Loxia 25, is largely because what makes this lens so essential is purely subjective. I’ll sum it up in a couple of sentences and a couple of photographs. Feel free to stick around for the slightly more technical rest, if that intro corresponds to your worldview 
Over the years, my love/hate relationship with my Sony bodies has fueled a strong motivation to look elsewhere for my photographic toolkit. Great performance on the one side marred by ergonomic lunacy and subpar (to put it very politely) colour management, on the other. While the Loxia range as a whole does sprinkle a little ergonomic fairy dust on its Sony hosts, what sets this 25mm f/2.4 apart for me is the almost complete cure of the chromatic vagueries of those cameras. A significant feat in my book.
I know it isn’t the case, but it looks like the Loxia 25 not only peels off a layer of yellow-green gunk from the sensor, but also extends its gamut in multiple directions. How? No idea. But the fact is that some synergy between my Sony A7r2 and the Zeiss Loxia 25 has divided my post-processing time by a significant amount and delivered results I didn’t think possible with that body.
Truth be told, my other lenses are all adapted lenses. And I’m pretty sure that native lenses do a better job of matching the Sony’s signature. But, having owned, reviewed or casually used quite a few of these native lenses, I’ve yet to fall in love with any of them! What makes this Loxia so special to me is that it brings subjective beauty to objective matching.
In the rest of this review, I won’t go into my usual technical breakdown of performance. Mainly because this has become a pointless exercise, now that almost any new lens on the market will give you enough resolution to create indecently large prints. But also because I was having so much fun making real pics that I kind of forgot to take actual test shots … some reviewer, right 
What I’ll do instead is try to break down the very high perceived quality of this lens into factual compartments with photographs to support each point. Ergonomics and build quality are usual Loxia, which is to say very nice, so I won’t go deeper into that aspect.
Colours
Let’s start with this lens’ most prominent asset.
Foliage is the usual downfall of the Sony with my other lenses. Greens very often take on a sickly yellow-orange cast, particularly in difficult light. No such problem here. And the subtlety of hues ranging from fresh green to elderly brown green is really very satisfying after years of mustardy landscapes that took ages to correct in PP.
Interestingly, many of the photographs on this page have had their saturation reduced in Capture One. Which is very rare for me. On some of these, I am finding the same level of beautiful neutrality as what the XCD 30mm offered on the Hasselblad X1D (complete review here).
That’s not to say the A7r2 is suddenly morphed into an X1D, but it does take a large leap in the right direction. And the good news remains true in varied light conditions and post-processing scenarios.
Sunstars
They look best at f/4 but work at other apertures. You get 10 spikes for your money. And they tend to be sharper and more beautiful on small sources of light than on very large ones. This is a lens that can turn specular reflections on water into a royal diamond necklace.
Transparency
If there’s an ISO standard for grading transparency, I’m not aware of it (which should come as no surprise to regular readers ) To me, transparency is the ability to faithfully recreate an atmosphere rather than impose a strong visual signature on it. This implies good resistance to flare, lack of chromatic and spherical aberrations, realistic 3D (including a linear shift from sharp to out of focus) and high colour and tone fidelity. All is usually well, even with mediocre lenses, when the sun is out and the scene is simple. But take your glass out during an overcast evening and make pictures of scenes with subtle shadings and you’ll soon sort out the men from the boys. It’s easy to produce a murky mess in those situations. Much harder to produce images with subtle hues and perfect 3D placement every little detail.
Here, the atmosphere is both beautiful and very true to life. The lens doesn’t appear artificially sharp, like some others in that focal range, nor does it feel mushy or overwhelmed by noise.
3D precision? You tell me As for chromatic aberration, it’s kept to an impressive minimum. While I don’t think Zeiss claim this to be an APO lens, it sure acts like one in most scenarios. In the scene below, shot at full aperture, only traces can be found around the wires cutting through the neon lights at top right.
Loxia 25 chromatic aberration at 100%
Contrast and sharpness
This may well be the most controversial aspect of this lens. While it is extremely sharp, it doesn’t look it. Rendering is soft and delicate by default. Compared to the much loved 55/1.8 (which I find overly aggressive) or the harsh Loxia 35, this is as mellow as port by the fireplace. To be honest, I’ve not had the time or inclination to test the lens extensively at multiple apertures. But I’m pretty sure that would be an exercise in futility with little bearing on the reality of making beautiful prints with this lens.
Here’s a full size jpg you can download to judge for yourself. It hasn’t been sharpened but I adjusted exposure. Please note that, for such a short focal length, the Loxia has a very shallow depth of field, even at f/5.6. The focus here is on the front buildings. So the background is actually out of focus, not unsharp
Output from the Loxia 25 simply looks refined. This level of refinement comes from an ability to resolve extremely fine detail. In MTF curves (measured, not calculated, as James Bond would require, were he a photo superhero) this is evident when the lower curve (that’s 40lp/mm, not 30) doesn’t fall down to the bottom of the graph. Most modern lenses bunch the first 3 curves (5 lp/mm, 10 lp/mm and 20 lp/mm) at the top. The 20 lp/mm struggles not to drift too far down the page and the 4th curve is really in the low figures. This gives a sharp look at lower magnifications but can’t convey the tiny details that create the subtle tones and 3D cues. As you can see from the (measured) Loxia 25 MTF curves, the worst case scenario (f/2.4 in the very corners) is above 40% contrast. The f/5.6 curve is in superlens territory. Also the curves are smooth with no sudden dips or deviations. Just looking at those tells you how well-behaved the lens will be in the field.
That the rendering is subtle and soft rather than aggressive and brash is a design choice that proves what niche Zeiss are targeting with the lens. And it certainly doesn’t mean photographs can’t be made to look super sharp in post processing, if that’s what you dig. But overall, this design is geared more towards atmosphere and ambiance than short term wow effect. To my eyes, it sits in between the Loxia 21 and the Loxia 85 (also a brilliant lens for colour subtlety but a tad more timid than the Loxia 25).
Bokeh
Bo-ke, the subjective quality of the unsharp areas of the photograph. Well, no 25mm f/2.4 lens is going to be a world leader in shallow depth of field, but the Loxia is remarkably shallow compared to, say, my Distagon 2/25 ZE.2 at equal apertures. So, how does this look in real life ?
Well, first of all, let’s keep it real. On any mid or long distance subject, the background is only going to look less sharp, not strongly out of focus. See above. It is only in situations where you are shooting at full aperture and close to minimal distance that you will throw the rest of the image into any significant measure of blur.
And, when you do, the background looks creamy smooth but remains very present. This is not a lens that makes out of focus areas vanish into a low contrast cappuccino. The background always sticks around to be a part of the story.
Negatives ?
A few, actually.
Mainly: I misfocused here and there.
- The automatic magnification of the view triggered by rotating the focusing ring is really pleasant, but it only enlarges 5x and you need to manually select the higher magnification setting to get best results systematically. You’d expect 5x to be perfect for such a short focal length but I’m not sure how accurate the focus assist tool is at that magnification, whereas it’s 100% reliable at 12,5x. That’s body related, but since this lens can’t be evaluated separately from the body, it’s worth noting.
- Even so, that speculative attack on the A7r2’s focus peaking accuracy isn’t enough to explain the various misses, as there is some very slight field curvature present so the focus and recompose technique may lead to misfocus due to the lens itself, not the body.
- Finally, I’m not 100% certain but feel the lens exhibits some minor focus shift, which makes it difficult to extract the very best performance out of it in low light.
All in all, not a biggie, but I did get a handful of duds out of roughly 1500 test shots.
Also, the lens cap is … well, really subpar. Sorry Zeiss. You should not have to scramble to attach the cap to the lens and, at that price level, the feel of the cap just isn’t on the same level as the rest of the lens (although it is a lot better on the Loxia range than on my ZM lenses). It’s a small thing, but small things are what matter in a luxury brand.
Optically, there’s not a lot to criticise. For some, the slightly soft default rendering could be an acquired taste but files respond well to sharpening and resolution is extremely high. This is a lens that preserves the data and lets you deal with it in PP rather than force a look upon the user.
If anything, and to be very picky, I’d cite distortion as a minor irk. It’s very minimal but never seems to correct perfectly well in Capture One. Is there a tiny wave there? I’m not sure. It’s invisible 99% of the time but for those exacting architectural shots, getting everything straight may be a smidgen more difficult than you’d hope for.
Conclusion
There’s a universal truth in marketing : it’s easier to sell pain killers than to sell fruit. Easier to sell the good people what they desperately think they want than to sell them what’s good for them. In recent years, the photographic market has turned into a display of technology and performance-on-paper in which the consumer has been educated to believe that more is better than good and crave technology over subjective optical quality. That getting the shot is more important than creating the shot.
f/1.4 is supposed to be better than f/2.4. AF is supposed to be better than manual focus. Fast AF is supposed to be better than slow AF. Cheaper is supposed to be better than expensive. Buttons everywhere are the new normal, regardless of the fact that 99.99% of the value of the lens is in its optical prowess and all of the above are largely detrimental to it.
The Loxia 25 is the sort of landmark anomaly that happens when you put aside the dominating market rules (a smart move, given how badly the market is performing as a whole) and just design for quality. Manual focus, easy to use, crisp, enjoyable and oh so lovely a photon bender. I’m not suggesting all lenses should be built on this model, other togs have different needs (heck, co-author Adam recently demonstrated what fabulous photographs can be made with a 7Artisans lens that is almost the antithesis of this Loxia 25), but I certainly am very grateful that it exists at all.
Compact, precise, exquisite, it is a light saber in an age of blasters.
Some years ago, Zeiss developed pivotal software that enabled them to simulate the rendering of a lens before building it, based on its optical formula. Ever since, the company has been pushing out winner after winner. In a market now dominated by the single metric of the MTF (the photo equivalent of the 0-60 figures for a car) and often sterile looks, this provides a middle ground between the soulless modern trend and the flawed but yummy best lenses of old. It delivers photographs that look good straight out of the box and need very little or no post processing, but also respond well to personal interpretation thanks to the richness of their data contents.
A lot of this has to do with the high quality files the Sony body provides when the conditions are ideal and I think this lens’ greatest merit is that it bonds so perfectly with the Sony that said conditions are always shiny. Anyone familiar with HiFi will know how two great components can complement or fight one another. The A7r2 and Loxia 25 are one copacetic happy marriage that never disappoints.
As I understand it, the Loxia 25 can be declicked for video use. Now, I wouldn’t recognise a video camera if it bit me on the arse, but still feel very confident that video users would be extremely happy with the level of visual refinement on offer here!
That the lens does in fact produce the high levels of quantitative performance expected of today’s offerings, and more, merely seems to be an inconsequential side product of a search for a much deeper and much more meaningful perfection, not only in isolation but mated to its host camera.
Kudos Zeiss. The Loxia 25/2.4 sure is a keeper !!
Posted on DearSusan by pascaljappy.