With the 135mm f/1.8 GM Lens, Sony continues to fill out their FE lens lineup and, simply put, this is an outstanding lens in all regards. If you can make the 135mm focal length work for your needs, you are going to want this lens in your kit.
Looking for an outstanding portrait lens? Want great low light performance? Need to get close to your subjects, making them large in the frame? Prefer your background blurred? Is accurate autofocus of value? Like to be impressed when reviewing your images? If any or all of those questions can be answered affirmably, the Sony FE 135mm f/1.8 GM Lens probably has your name on it.
The focal length determines the angle of view taken in by the lens and it is, therefore, an important consideration for lens selection. This choice establishes the subject distance required for the desired subject framing with that distance determining the perspective achieved.
While a zoom lens provides a broad range of focal lengths, a prime lens has only one. This means that focal length selection for a prime lens is far more critical than for a lens featuring a wide range of focal lengths, a zoom lens. What is the 135mm focal length good for? Among numerous other applications, I find portraits to be the standout 135mm focal length use.
This telephoto focal length, on either a full frame or APS-C crop sensor format DSLR, pushes the focus distance far enough to provide an ideal portrait perspective. Even when used for tightly framed head shot portraits, 135mm retains a pleasing look.
This head shot was not close to this lens' minimum focus distance, but it illustrates nice feature compression and provides a peek at the background blur this lens excels at.
The "portrait photography" designation is a broad one that covers a wide variety of potential still and video subject framing (from full body to head shots) and a wide variety of potential venues (from indoors to outdoors). Portrait subjects can range from children to seniors and from individuals to groups (though large groups will require a rather long working distance with a 135mm lens). Basically, whenever people are present, this lens has uses. Think engagements, weddings, parties, events, families and small groups (when adequate working space is available), senior adults, fashion, documentary, lifestyle ... all are great uses for the 135mm focal length.
Interesting (to me at least) is that I had a high school senior in the house when I reviewed the last 135mm f/1.8 lens (Sigma) and I also have a senior in the house while reviewing this one. So, I can say the same thing over: With my own senior in the house, I didn't have to look very far for a 135mm f/1.8 lens portrait subject (though her schedule was an issue this time). In case you haven't noticed, kids have this issue called "growth" and it happens unbelievably fast. And, "growth" can conveniently be stopped by this thing we call "photography". Apply "photography" liberally within your family and the families of others so that we can contain the growth issue. If you've hung around here for very long, you know that I take my own advice in this regard and am grateful to have so many pictures of the kids to take them back in time.
Unfortunately, the amount of time I had this lens overlapping my daughter's availability was short, but we did manage to get a short portrait session in.
People participate in sports and this is a great sports photography lens. With an ultra-wide aperture, this lens is an especially great choice for capturing indoor sports.
Practically every lens can be used for landscapes, but the Sony FE 135mm f/1.8 GM Lens is an incredible option for this use. While the 135mm focal length may not seem like a staple in a landscape photography kit, it is a great one to have available for a more-compressed landscape look. And, the incredible image quality this lens delivers means that even the tiniest landscape details are tack sharp, including the extreme corners. A telephoto lens can fill the frame with color from even mediocre sunsets.
Pets and other tame animals can make good 135mm subjects.
A 135mm lens can be used for many other purposes including product and commercial photography along with general studio applications. With a strong maximum magnification spec, this lens is great for small through large product photography. Videographers will find many uses for this lens.
Those using the 135mm focal length on an ASP-C/1.5x FOVCF sensor format camera will have a narrower angle of view to work with, one equivalent to a 202.5mm focal length used on a full frame camera. While this angle is similarly useful, the uses push toward tighter portraits, smaller products, more-compressed landscapes, and away from more-general purpose uses.
Similar to what I said when reviewing the Sigma 135mm f/1.8 lens, from the front, the Sony FE 135mm f/1.8 lens strongly resembles a pipe. There is a lot of open space inside this lens.
While many alternative 135mm prime lenses feature an f/2 max aperture, this Sony 135mm lens opens up another 1/3 stop to f/1.8, giving it the widest max aperture available in a 135mm lens as of review time (equal to the Sigma 135mm f/1.8 DG HSM Art Lens and the Sony Sonnar T* 135mm f/1.8 ZA Lens).
The rule is that the wider the aperture, the more light that is able to reach the imaging sensor. More light reaching the sensor means that faster shutter speeds can be used and subject and camera motion can be stopped in lower light circumstances. With the f/1.8 aperture available, handholding this lens remains possible even in low light levels. This wide aperture is especially valuable after the sun sets, shooting under shade conditions, and indoors using only ambient window light. On the day of the above-referenced senior session, the camera settings were about 1/160 and ISO 100 with the f/1.8 aperture in use.
The shallow f/1.8 depth of field must, of course, be acceptable to you in these circumstances, but that shallow depth of field is a very-highly desired lens capability, excellent for isolating a subject against a strongly-blurred background. The wide f/1.8 aperture combined with the 135mm focal length used at a close focus distance will turn even the most distracting background into a blur of colors. The shallow DOF provides a three-dimensional look and can eliminate even the ugliest background distractions. The blurred background effect draws the viewer's attention to the subject and this look will cause your imagery to stand out from the crowd.
The extremely shallow depth of field capability adds artistic-style imaging to this lens' strong capabilities list.
Here is a look at the aperture range of this lens:
The background in this image is completely erased at the wider apertures. To better illustrate the wider aperture differences, I should have created this comparison with a closer background. View the example set provided in the Sigma 135mm f/1.8 DG HSM Art Lens review for another look at these differences. The difference in background blur at f/1.8 vs. f/2 is noticeable.
Here is another look at the extreme blur this lens can create.
It should be noted that, especially under full sun conditions, a 1/8000 shutter speed may be only marginally fast enough to avoid blown highlights at f/1.8. Cameras with shutter speeds limited to 1/4000 may need the assistance of a neutral density filter to keep images dark enough at f/1.8. Shooting with a narrower aperture, of course, remains an option.
Sony has been featuring an aperture ring on some of their prime lenses including this one, permitting a manually-chosen aperture to be selected. With the ring in the A (Auto) position, the camera controls the aperture setting. All other settings force the aperture to the selected opening and a 2-position switch on the bottom right side of the lens toggles the aperture ring between 1/3 stop clicks and smooth, quiet, non-clicked adjustments, ideal for video recording. The aperture is electronically controlled by the ring.
Aside from a slightly more complicated design, perhaps the primary disadvantage of an aperture ring is that inadvertent aperture changes can be made. Making the A click stop firm enough to prevent inadvertant changes eliminates much of that concern.
There are notable drawbacks to lenses that feature very wide maximum apertures. These lenses require the use of larger, heavier glass elements which translate into larger and heavier lenses. Unfortunately, those larger elements are not only evidenced by the increased weight, but also by the increased price of the lens. That said, compared to its peers, this lens is not large or heavy. The price tag is rather high, but not extremely so.
For most photographers, the benefits of a wide max aperture prime lens far outweigh the drawbacks. Usually, no flash is required.
The Sony FE 135mm f/1.8 GM Lens is not optically stabilized, but Sony takes care of that issue with Steady Shot or IBIS, the acronym for "In-Body Image Stabilization". On a traditional DSLR with an optical viewfinder, IBIS results in an unstabilized view, meaning that stabilization was not helpful for composition or for providing a still subject to the camera's AF system. With EVFs being prevalent in Sony's lineup, the viewfinder and AF-based image are being read from the imaging sensor – which is stabilized. Therefore, when the 135 f/1.8 GM is used on one of these cameras, the image seen in the viewfinder and seen by the autofocus system is very nicely stabilized.
Mounted on a Sony a7R III with Steady Shot enabled and shooting in ideal conditions (indoors, solid floor), I was able to handhold this lens with a high percentage of sharp results down to a 1/15 second shutter speed. A solid percentage captured at 1/13 second were sharp and most images captured at shutter speeds longer than 1/10 second were not.
Again, this testing was under ideal circumstances and your results will vary dependent on your own skills and the conditions you are shooting in, but IBIS contributed very nicely to the handholdability of this lens. Combine f/1.8 with IBIS and it seems that this lens can be handheld in even the darkest circumstances (as long as the subject is relatively still — image stabilization does not stop subject motion), greatly aiding the versatility of this lens.
While focal length and the available aperture range are crucial lens selection factors, it is image quality that often makes or breaks a lens choice. Likely none are going to take this lens off of their short list due to image quality issues — Sony FE 135mm f/1.8 GM Lens image quality is simply awesome.
So often when buying an ultra-wide aperture prime lens, the wide-open image quality is not that great. Great is that from full frame corner to corner, even wide-open at f/1.8, this lens turns in exceptional image sharpness (contrast and resolution). Aside from depth of field increasing and mild vignetting clearing, there is little change imparted by using a narrower aperture and none is needed. At f/1.8, this lens has outstanding image quality.
Taking this lens outdoors, we see the same results. The images below are 100% resolution center-of-the-frame crops from images captured in uncompressed RAW format using a Sony a7R III. The images were processed in Capture One using the Natural Clarity method with the sharpening amount set to only "30" on a 0-1000 scale (Note that images from most cameras require some level of sharpening but too-high sharpness settings are destructive to image details and hide the deficiencies of a lens).
Be sure to find details in the plane of sharp focus to base your opinions on. The eye sample is from the vertical portrait shown earlier in the review. With this lens, the wide-open aperture can be used whenever desired without sacrificing image quality.
Focus shift, the plane of sharp focus moving forward or backward as the aperture is narrowed (residual spherical aberration or RSA), is not an issue when using this lens.
Next, we'll look at a comparison showing 100% extreme-top-left-corner crops captured and processed identically to the above center-of-the-frame images. These images were manually focused near the corner of the frame.
The corner resolution this lens delivers is quite impressive and vignetting clearing is primarily what is seen here.
Does corner sharpness matter? Sometimes it does, sometimes it doesn't. When it does, this lens is ready.
When used on a camera that utilizes a lens' entire image circle, peripheral shading can be expected at the widest aperture settings. At f/1.8, this lens has about-2-stops of shading in the corners. This amount is average for the class, often noticeable but not too strong. To reduce peripheral shading, stopping down is the strategy that usually works. With an only 1/3 stop narrower aperture, the corner shading is already reduced to 1.6-stops. By f/2.8, the shading is going below 1-stop, the amount often used to mark visibility in most images. At f/5.6, the vignetting levels off at a seldom-visible about-0.4-stops.
APS-C format cameras using lenses projecting a full-frame-sized image circle avoid most vignetting problems. In this case, the about-1-stop of shading showing at f/1.8 might be visible in images with a solid color (such as a blue sky) showing in the corners.
Vignetting can be corrected during post processing with increased noise in the brightened areas being the penalty or it can be embraced, using the effect to draw the viewer's eye to the center of the frame.
The effect of different colors of the spectrum being magnified differently is referred to as lateral (or transverse) CA (Chromatic Aberration). Lateral CA shows as color fringing along lines of strong contrast running tangential (meridional, right angles to radii) with the mid and especially the periphery of the image circle showing the greatest amount as this is where the greatest difference in the magnification of wavelengths typically exists.
While lateral CA is usually easily corrected with software (often in the camera) by radially shifting the colors to coincide, it is better to not have the problem in the first place. Any color misalignment present can easily be seen in the site's image quality tool, but let's also look at a worst-case example, a 100% crop from the extreme top left corner of an ultra-high resolution a7R III frame showing diagonal black and white lines.
There should be only black and white colors in these images and the additional colors are showing lateral CA. In this case, the additional colors are very slight.
A relatively common lens aberration is axial (longitudinal, bokeh) CA, which causes non-coinciding focal planes of the various wavelengths of light, or more simply, different colors of light are focused to different depths. Spherical aberration along with spherochromatism, or a change in the amount of spherical aberration with respect to color (looks quite similar to axial chromatic aberration but is hazier) are other common lens aberrations to look for. Axial CA remains at least somewhat persistent when stopping down with the color misalignment effect increasing with defocusing while the spherical aberration color halo shows little size change as the lens is defocused and stopping down one to two stops generally removes this aberration.
In the real world, lens defects do not exist in isolation with spherical aberration and spherochromatism generally found, at least to some degree, along with axial CA. These combine to create a less sharp, hazy-appearing image quality at the widest apertures. In the examples below, look at the fringing colors in the out of focus specular highlights created by the neutrally-colored subjects. Any other color there is being introduced by the lens.
While I see some color separation, the amount is quite modest.
Flare is caused by bright light reflecting off of the surfaces of lens elements, resulting in reduced contrast and interesting artifacts. The shape, intensity, and position of the flare in an image is variable and depends on the position and nature of the light source (or sources) as well as on the selected aperture, shape of the aperture blades and quality of the lens elements and their coatings. Sony's Nano AR Coating is used to "eliminate" flare and ghosting. While the word "eliminate" by full definition is a bit of a stretch, this lens performs extremely well in this regard, arguably the best in its class. With the sun in the corner of the frame, only slight flare effects are seen at narrow apertures (f/11 and f/16).
There are two lens aberrations that are particularly evident when shooting images of stars, mainly because bright points of light against a dark background make them easier to see. Coma occurs when light rays from a point of light spread out from that point, instead of being refocused as a point on the sensor. Coma is absent in the center of the frame, gets worse toward the edges/corners, and generally appears as a comet-like or triangular tail of light which can be oriented either away from the center of the frame (external coma) or toward the center of the frame (internal coma). Astigmatism is seen as points of light spreading into a line, either meridional (radiating from the center of the image) or sagittal (perpendicular to meridional). Remember that lateral CA is another aberration apparent in the corners.
The image below is a 100% crop taken from the extreme top-right corner of an a7R III frame.
These stars are not rendered perfectly round, but they are rounder than the stars produced by most other lenses.
With only one focal length to be designed for, prime lenses tend to have very low geometric distortion and that is the case with this lens. I see a slight amount of pincushion distortion, but it will not be visible in most scenarios.
The blur and quality of blur seen in the out of focus portions of an image are referred to as bokeh. Easy to establish is that this lens can create a very strong background blur. Following are some examples showing the quality of that blur.
At f/8, with the 11-blade aperture narrowed by 4-stops, out-of-focus specular highlights are nicely rounded with a smooth center. The two f/5.6 full images reduced in size show very nice results. The f/1.8 example is also a full image, illustrating the cat's eye effect, a form of mechanical vignetting, seen in the periphery at the wide-open aperture setting. This amount is normal.
When stopped down, this lens' 11-blade aperture produces reasonable-looking 22-point stars from point light sources
The Sony FE 135mm f/1.8 GM Lens design includes an extreme aspherical lens (XA lens) (orange), Super ED (Extra-low Dispersion) glass (blue), and ED glass (green).
The optical designers of this lens should be commended as they have created a lens that produces outstanding image quality.
The 135 f/1.4 GM lens utilizes dual XD linear motors as the foundation of its AF system.
This system focuses very smoothly and quietly, with a faint whir and sometimes rapid clicks heard during AF if a stopped-down aperture is being used (with this lens and the current Sony a7R III firmware, the aperture is opened during AF, the source of the mentioned clicking sounds).
Note the Sony a7R III (and most/all other current Sony MILC cameras) will de-focus the lens slightly before focusing on the subject, even if focusing to the focus distance already established and even with the same motionless subject. This technique impacts AF lock time, though this lens still locks focus very fast in AF-S mode, especially with a wide-open aperture being used. Sony full frame MILC's show the set aperture in the viewfinder, having some benefits including a constant depth of field preview, but as mentioned, the lens' aperture is fully opened during AF.
The Sony 135mm f/1.8 GM Lens focuses internally with, extremely important when depth of field is shallow, impressively-consistent accuracy, including when human and animal eye AF continuous focus modes are used.
Sony provides AF hold buttons on many of their lenses and this lens has two of them, conveniently located on the top and left side. These positions are convenient for the left thumb access when using the camera in both horizontal (grip to the right) and vertical orientation (grip up). While in continuous focus mode, this button can be pressed to lock focus at the currently selected focus distance, permitting a focus and recompose technique. This button also acts as a custom button (C5) and can be programmed to another function using the camera's menu (note that not all models are supported).
FTM (Full Time Manual) focusing is supported via Sony's DMF (Direct Manual Focus) AF mode.
The rubber-coated manual focus ring is nicely sized, is very smooth, is ideally dampened and the about-80° of rotation is just right for precise manual focusing at all distances.
This lens produces a rather strong change in subject size during a full extent focus adjustment. While this attribute is not unusual, photographers intending to use focus stacking techniques involving focus distance adjustment, videographers pulling focus, and anyone very-critically framing a scene should be aware.
While focus distance marks are not provided, a focus distance meter shows in the lower portion of the electronic viewfinder during manual focusing.
This lens features a focus range limit switch that, in addition to making the full focus range available, enables focus distance selection to be limited to 2.30' (0.7m) - 6.56' (2m) or 4.92' (1.5m) - ∞. When the subject is known to stay in one of the limited ranges, this feature can potentially decrease focus lock times.
With a 27.6" (700mm) minimum focus distance, the Sony FE 135mm f/1.8 GM Lens posts a (tied-for) best-in-class 0.25x maximum magnification spec with only the Zeiss Milvus 135mm f/2 Lens rivaling it at this time.
|Canon EF 135mm f/2L USM Lens||35.4"||(900mm)||0.19x|
|Nikon 105mm f/1.4E ED AF-S Lens||39.4"||(1000mm)||0.13x|
|Sigma 105mm f/1.4 DG HSM Art Lens||39.4"||(1000mm)||0.12x|
|Sigma 135mm f/1.8 DG HSM Art Lens||34.4"||(875mm)||0.20x|
|Sony FE 135mm f/1.8 GM Lens||27.6"||(700mm)||0.25x|
|Zeiss 100mm f/1.4 Otus Lens||39.4"||(1000mm)||0.12x|
|Zeiss 135mm f/2 Milvus Lens||31.5"||(800mm)||0.25x|
A subject measuring approximately 5.5" x 3.7" (138 x 94mm) will fill the frame at the minimum focus distance. The coneflower in the aperture comparison earlier in the review measures about 2" (50mm) in diameter and the lily in the image below measures about 6" (150mm) in diameter.
Photograph the wedding rings in the bouquet of flowers or details on the dress.
Not only can this lens focus very closely but it delivers very sharp results wide-open at f/1.8 at minimum focus distance. Below is a 100% crop taken from an image captured at minimum focus distance.
Need a shorter minimum focus distance and greater magnification? An extension tube mounted behind this lens should provide a reasonable improvement. Extension tubes are hollow lens barrels that shift a lens farther from the camera, which permits shorter focusing distances at the expense of long-distance focusing. Electronic connections in extension tubes permit the lens and camera to communicate and otherwise function as normal. Sony does not publish extension tube specs nor do they manufacture these items, but third-party Sony extension tubes are available.
This lens is not compatible with Sony teleconverters.
The G Master lens series represents Sony's best-available lenses. These lenses are designed and built for the rigors of professional use.
Roger Cicala tore an FE 135 GM lens down and now we can be certain that this is a well-designed, ruggedly-built lens. Typical is for a lens family to share design traits and here we can see the same.
Here is a closer look at this lens.
Sony FE lenses have a rather narrow mount and by design, that means a rather abrupt and significant diameter increase starting at just under 1" (25.4mm) into the lens. A small diameter increase occurs at the aperture ring and another small increase tactilely designates the start of the focus ring. The outer lens barrel construction is engineering plastic.
Sony focus rings make distance adjustments by turning in the same direction as Canon lenses (the opposite of Nikon lenses).
Overall, this lens' build quality feels nice with all rings and switches having a precision feel to them. The AF/MF switch is recessed, making it hard to inadvertently change and requiring a bit more effort to intentionally change it, especially with gloves on.
This is a great lens for outdoor use and a dust and moisture-resistant design, including a gasketed mount, can save the day out there. Don't confuse weather sealing with waterproof — the owner's manual states: "This lens is not water-proof, although designed with dust-proofness and splash-proofness in mind. If using in the rain etc., keep water drops away from the lens."
Few are going to consider this lens small and light, but it is not large and heavy either. This is a mid-sized lens that is comfortable to hold and use for reasonably long periods of time. After shooting fast action for over an hour, I started to feel some mild tiring of my grip fingers, the last three digits of my right hand.
|Model||Weight oz(g)||Dimensions w/o Hood "(mm)||Filter||Year|
|Canon EF 135mm f/2L USM Lens||26.5||(750)||3.3 x 4.4||(83.0 x 112.0)||72||1996|
|Nikon 105mm f/1.4E ED AF-S Lens||34.8||(985)||3.7 x 4.2||(94.5 x 106.0)||82||2016|
|Sigma 105mm f/1.4 DG HSM Art Lens||57.9||(1640)||4.6 x 5.2||(115.9 x 131.5)||105||2018|
|Sigma 135mm f/1.8 DG HSM Art Lens||39.9||(1130)||3.6 x 4.5||(91.4 x 114.9)||82||2017|
|Sony FE 135mm f/1.8 GM Lens||33.5||(950)||3.5 x 5.0||(89.5 x 127.0)||82||2019|
|Zeiss 100mm f/1.4 Otus Lens||49.6||(1405)||4.0 x 5.1||(101.0 x 129.0)||86||2019|
|Zeiss 135mm f/2 Milvus Lens||39.6||(1123)||3.5 x 4.5||(89.7 x 115.0)||77||2016|
For many more comparisons, review the complete Sony FE 135mm f/1.8 GM Lens Specifications using the site's Lens Spec tool.
While this lens is very nice to hold and use, at review time there is a camera problem to contend with. For those with hands the size of mine (upper-side-of-medium-sized) or larger, Sony's current MILC cameras (such as the a7 III, a7R III, and a9) provide an inadequate grip size. There is not quite adequate room for fingers to fit between the camera and the lens. Near the edge of the primary diameter increase, the lens presses into the first joint of my middle finger when the camera is gripped surely. Of course, the lens is not soft and that means the grip is not comfortable. The pressure is lessened if the lens is hanging downward from a loose grip or if I rotate my grip away from the lens, but ... that does not give me the grip assurance I would like to have. This issue applies to all but the smallest Sony lenses I've reviewed to date. Smaller hands avoid this problem.
I always find it helpful to visually compare the size of lenses and here we see the Sony nicely fitting into its group. Remember that we align lenses on their mount flanges and that the Sony rear lens caps are rather short.
Positioned above from left to right are the following lenses:
The same lenses are shown below with their hoods in place.
Use the site's product image comparison tool to visually compare the Sony FE 135mm f/1.8 GM Lens to other lenses.
Add another lens to the list of those utilizing 82mm filters. Not terribly long ago, this was not a popular filter size but today 82mm is quite common among high-quality lenses including the Sony FE 135mm f/1.8 GM Lens. Filters of this size are not inexpensive or small but they likely can be shared between the lenses in a pro-grade kit. Lenses with smaller filter threads can utilize 82mm filters using a step-up filter adapter ring.
The Sony ALC-AH156 Lens Hood is included in the box. This semi-rigid plastic hood has a flocked interior for superior reflection avoidance (and slightly increased cleaning difficulty) and a push-button release makes the bayonet mount easy to use. The rounded shape means you can stand the lens on that end, even with the camera attached (in situations where you are comfortable with that). Nice is that the end of the hood is rubberized, protecting both it and what it is against from scratches and making it less likely to slide. The rubber is also nice to have when bracing the camera against something to steady the shot. And, I think it looks nice.
Sony includes a nice zippered, padded nylon lens case in the box. This case has a belt loop sewn onto the back and a shoulder strap is provided.
You will not often hear a Sony lens being called cheap and this one carries a significantly high price tag, one high enough to be a barrier to the non-enthusiast and non-professional. This is, however, a really impressive lens in all regards and thus easily justifies its price.
As an "FE" lens, the Sony FE 135mm f/1.8 GM Lens is compatible with all Sony E-mount cameras, including both full frame and APS-C sensor format models. Sony provides a 1-year limited warranty.
At review time, this lens model could not be found in retail stock. A short-term loan from Sony was required to put a Sony FE 135mm f/1.8 GM Lens in my hands for this review.
Offered in a native Sony E-mount and, at review time, most strongly competing against this Sony lens is the Sigma 135mm f/1.8 DG HSM Art Lens. In the image quality comparison, these two lenses appear very similar. If forced to determine a winner, I'd go with the Sony by a hair. The Sigma has slightly less vignetting, very slightly less linear distortion, and shows slightly more flare.
Looking at the specs and measurements, the Sony FE 135mm f/1.8 GM Lens vs. Sigma 135mm f/1.8 DG HSM Art Lens comparison shows the Sony lens weighing slightly less and measuring slightly longer while the Sigma lens has a modestly wider diameter. The Sigma lens has a larger focus ring with a longer throw. The Sony lens has 11 aperture blades vs. 9, has an aperture ring, and has focus hold buttons. The Sony lens has a shorter minimum focus distance that yields a higher maximum magnification (0.25x vs. 0.20x). Certain to be a decision factor is the Sigma's significantly lower price tag.
Put a group of Canon-based photographers in a room and likely the Canon EF 135mm f/2L USM Lens will be on their list of favorite lenses. Obviously, the Canon lens is short 1/3 stop of max aperture in this comparisons and the image quality comparison shows the 23-year-older lens also coming up short against the Sony. The Sony lens shows less flare.
Looking at the specs and measurements, the Sony FE 135mm f/1.8 GM Lens vs. Canon EF 135mm f/2L USM Lens comparison shows the Canon lens to be modestly lighter and smaller (but with a larger lens hood). The Sony lens has 11 aperture blades vs. 8, has an aperture ring, and has focus hold buttons. The Sony lens has larger threads, 82mm vs. 72mm and the Canon lens is not weather sealed. The Sony has a shorter minimum focus distance that yields a higher maximum magnification (0.25x vs. 0.19x). The Canon lens is compatible with extenders, adding to its versatility. The Sony lens' approaching 2x-higher price tag leaves an impression in this comparison, but the Sony does come with a nicer case.
The Zeiss 135mm f/2 Milvus Lens is a very option that is adaptable to the Sony mount. In the image quality comparison, the Sony lens produces slightly better center of the frame image quality while the Zeiss is at least as good or perhaps slightly better in the corners. The Zeiss lens has slightly less linear distortion.
Looking at the specs and measurements, the Sony FE 135mm f/1.8 GM Lens vs. Zeiss 135mm f/2 Milvus Lens comparison shows the Zeiss lens to be slightly shorter but slightly heavier. The Sony lens has 11 aperture blades vs. 9 and has an aperture ring. The Zeiss lens has a larger focus ring with a much longer throw. The Sony lens has larger threads, 82mm vs. 77mm. Price is not a strong differentiator between these two lenses, but reducing versatility is that the Zeiss lens is manual focus only.
When a lens is as well-designed as this one, the purchase (or rent) decision comes down to whether or not the provided focal length is a useful addition to the kit and whether or not the price tag can be afforded.
Addressing the first question, the 135mm angle of view is perfect for portraits, ideal for some sports, and excellent for product images. Addressing the last question, sometimes you get what you pay for and in this case, I don't think you overpay.
At review time, the max aperture at 135mm doesn't get wider than this. The Sony 135mm f/1.8 GM is ready for stopping low light action with a distinguishing and artistic background blur readily available. Autofocus performance is superb, ensuring the potentially very shallow depth of field is properly aligned on your subject. This lens' build quality leaves little to want. The image quality produced by this lens places it in an elite category. What did I miss?
This lens is good enough to justify the purchase of a Sony E-mount camera just to use it on.
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