So let’s get one thing straight from the beginning, comparing these two lenses is not about finding out which of the two are the best lens in absolute terms. Optically the Loxia is, as expected, the better lens in most aspects. It is after all a world class prime. On the other hand the Sony Zeiss FE 16-35mm/4 has a few tricks on it’s own that the Loxia can’t match. It can autofocus, it has built in stabilization and it can of course zoom. Three traits that can be very convenient. And it’s no slouch optically either (especially at the short end), being as good as the equivalent Canon and Nikon offers.
I’ve had the zoom for a little over a year now and used it a lot. It has always delivered but there has always been a little friction. Manual focus is tedious and there has been something with the pictures that hasn’t resonated with my eye. I have been pleased with the performance but not perhaps happy.
The Zeiss Loxia 21mm has gotten raving reviews, and I have more than a few old Zeiss Contax lenses that I love, so in February I had convinced myself that life had ceased to have any meaning without one on my camera.
Even if 21 mm is a very natural focal length for me, ditching the zoom would mean adding two or three more primes to my camera bag. First something in the order of 15 or 16 mm for those ultra, ultra wide shots and then either a 28 mm or 35 mm or perhaps both. Carrying around three or four primes instead of a zoom would add to both weight, space and handling.
So for me the Loxia would have to add something special to overcome the advantages of the zoom.
Build and feel
The zoom feels well built and gives you a nice feeling of quality when holding it. At a length of 98.5 mm, a width of 78 mm and a weight of 518 g it also feels pretty small and manageable for a autofocus zoom with stabilization.
Tolerances are tight and everything moves smoothly with a nice resistance. The focus ring is a fly-by-wire design so there is no stops at infinity and close focusing. The zoom ring feels good with nice resistance. There is no aperture ring, aperture is set from the camera.
Filter diameter is 72 mm and at a focal length of 21 mm you can put on two filters without vignetting. At 16 mm you need to take one of those off to not get hard cut-offs at the corners.
If the zooms build feels good the Loxia feels like a piece of art. It’s much smaller with a width of 62 mm and a length of 72 mm. But it feels dense with a wight of 394 g. And it probably is because as far as I know there is very little plastic, if any, inside. Filter thread is 52mm and you can use one filter without hard vignetting in the corners. 52 mm is the same as the other lenses in the Loxia series so you can share filters if you have more than one. Tolerances are very tight and the focus ring is smooth with just about the right resistance and no hint of play. The aperture ring likewise is perfect with distinct but not to hard stops.
The FE 16-25 mmm f/4 zoom comes with a plastic hood than snaps onto the front of the lens and plastic front and back caps. All working as they should.
The Loxia comes with a beautiful metal hood that also snaps onto the front, a standard plastic back cap and a plastic front cap of absolutely ridiculous low quality. A $1 no-name cap from Ebay is like luxury compared. Inconsistent and unnecessary on a $1500 lens.
Both lenses handles well on my A7SM2. The Loxia is of course smaller but balances well being so dense. The zoom is of course a lot bigger but I have no problems walking about with either of the lenses.
A word of caution for the Loxia. Since there is very little on the lens barrel that is not moving (focus and aperture ring), mounting and un-mounting the lens can feel a bit insecure. Be sure to check that the lens actually has clicked and locked when mounting. It has happened to me that it was just turned half way, with the risk of coming loose and dropping to the floor. Now I always check one extra time.
Some things should be mentioned about focusing since this is something that differs a lot on the lenses.
The Loxia 21mm is strictly manual but there is an electric coupling so that the focus magnifier becomes active when you turn the focus ring. Personally I love this and it helps me focus fast and accurately, but I know it’s not for everyone. It can turned off in the camera menus.
The autofocus in the FE 16-35 f/4 zoom works very well. It’s fast and accurate. It’s also almost silent so video with autofocus is not a problem.
Focusing manually on the zoom is another, more depressing story. First of all it’s a fly by wire design so there is no hard stops. Then it’s not a linear, the faster you move the focus ring the faster the focus is changed. My brain can’t learn this so there is always a lot of turning back and forward before finding focus.
Setting hyperfocal distance on the zoom is also not straight forward. There are no markings on the lens so you have to watch the screen or viewfinder to see the distance. Not the fastest way to work.
The Loxia on the other hand has clear distance and depth of field markings on the lens. Setting the hyperfocal distance is a matter of seconds.
Sharpness and micro contrast
These pictures were taken with a tripod and self release on my Sony A7SM2. Both were 1/250 sec, f11 and ISO200 and white balance was identical. Since I usually shot landscape I seldom use larger aperture than f8. I would expect that both lenses would perform very good on these settings.
They were imported to Photoshop with ACR, without any processing like sharpening or lens correction, and then saved as max quality jpegs.
Both lenses are very sharp in the center, probably outperforming the sensor by a wide margin. I think the perceived sharpness is a little bit better with the Loxia because of the better micro contrast. This is best seen in the grain and texture of the wood where the Loxia is able to render much more detail. And also in the dark background.
In the image border there is still very good sharpness from both lenses. I think it’s hard to tell who is the sharpest. It depends on where you’re looking. Perhaps the Loxia has the edge on contrast.
Both lenses are still performing very good in the corner in my opinion. The Sony is perhaps losing a little contrast and there is som slight CA.
So, in terms of sharpness, at least on my 12 megapixel sensor there is very little difference. The difference I can see is the overall better micro contrast from the Loxia giving the image a better punch, livelier textures, shadows and clouds and overall more impact. A little more perceived sharpness perhaps.
I’ve never had any real world issues with CA on either of the lenses. Both can also be corrected, both in-camera and in Adobe Camera Raw or Lightroom
I would say the color rendering from the lenses differ very much. The Sony zoom is quite yellow with skies leaning towards cyan, sea towards green and reds towards orange. The Zeiss Loxia is colder with more more magenta in the skies rendering them bluer, rather than cyan. The sea is more neutral and reds are also rendered more towards magenta.
Color is very subjective of course but personally I like the rendering of Zeiss Loxia very much. They feel more a bit cooler and more natural, corresponding with what I saw when taking the pictures.
Actually, the colors of the zoom is something that has been bothering me. Even though I couldn’t put my finger on it, there always been something that never felt really right. Doing this comparison has made me aware that I’m not fully satisfied with the color rendering of the FE 16-35 f/4.
Below are an example of how different the sky and clouds are in color (click for full resolution)
I think I never had a lens that performs better against the sun than the Loxia 21 mm. You can put the sun anywhere with almost no veiling. If you really provoke it you can get a few small yellow-greenish ghosts on the opposite side of the sun as in the example below
The Sony zoom is much more prone to flare. With the sun in the frame you have to take good care not to ruin your shot with large ghosts both side of the sun.
These pictures are also a good example of the sunstars you can expect.
The Loxia has notably more fall-off in the corners even when stopped down to f/8 or f/11. At f/2.8 it’s clearly visible and can make a difference in the real world. From f4 it is much more manageable.
The FE 16-35 mm f/4 zoom performs very good. Fall-off at 21 mm is never more that 1 stop no matter what aperture and less for the most.
Both lenses can also be corrected, both in-camera and from profiles in Adobe Camera Raw or Lightroom.
At 21 mm the FE 16-35 mm f/4 zoom has almost no distortion at all. Very good.
The Loxia 21mm has a little barrel distortion with a tendency of waviness. For landscapes this would not be a problem but for architecture you probably want to correct it. This can bi done in-camera or with profiles in Adobe Camera Raw or Lightroom.
Let’s start with saying that both lenses are very good, optically there is less difference than what I thought it would be. There might be a larger difference on a higher resolving sensor.
So what lens you choose is up to your needs and preferences. Personally I’m going to stay with the Loxia. The tipping points are flare control, slightly better micro contrast, manual focus performance and the, in my opinion, much better color rendering.
So now I need to find a as good 15 mm and then I’ll let the zoom go.
These samples are post-process to taste (Click for hi-res versions)
All photos copyright: Lasse Thomasson 2017