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Alternatives to the Sigma 12-24mm f4 DG HSM Art Lens

As discussed early in this review, the 12-24 has few direct competitors, at least few that go as wide as 12mm.
The primary non-Sigma competitor is the Canon EF 11-24mm f/4L USM Lens and this was the lens I was anxious to put the Sigma up against.
Would the Canon be worth the over-40% price premium?

From an image sharpness perspective, the
Canon bests the sigma.
The Canon wins all comparisons at f/4 and is significantly sharper at 24mm f/4.
Stopped down, the differences narrow, but the Canon generally produces sharper image quality even at f/8.
The Canon has more latCA at the wide and mid portions of the focal length range and also has noticeably more vignetting over that similar focal range at f/4, though the differences are essentially erased by f/8.
With a front element that does not extend and retract, the Canon is better weather sealed.
The Sigma has a higher MM, (0.20x vs. 0.16x)
The Canon’s 1mm wider focal length may not sounds like much, but it is a noticeable difference.
The Sigma’s focus shift attribute is another considerable difference.

The other lens that begs for a comparison is the 12-24mm f/4.5-5.6 DG II HSM Lens, Sigma’s previously-released 12-24mm model.
Here is a visual comparison of these two lenses:

Although the design of the Art lens is not dramatically different, the f/4 model is considerably larger and heavier.
And, the Art’s price has grown even more than its weight, making the II appear to be a great bargain.

Is the Art lens’ wider aperture useful? For some, the answer is «Yes.» For others, not at all.
Far more convincing in this decision making process is the
image quality comparison.
The Art lens handily bests the II in all wide open (matching aperture) comparisons, especially in the corners.
The difference remains rather obvious even stopped down to f/8.
The Art lens has less considerably less vignetting wide open and still less at f/11.
The Art lens has less distortion.
Overall, the Art lens is a very significant upgrade to the II, but that gain is not without financial cost.

There are many more comparable lenses available, but no options offer a rectilinear focal length wider than 14mm.
Use the site’s lens comparison tools to make your own comparisons of these lenses.

Focusing

The 12-24mm Art Lens gets Sigma’s best AF system, called HSM (Hypersonic Motor).
At normal focus distance changes, AF locks on the subject nearly instantly.
Do a full extent AF adjustment, from near minimum focus distance to infinity or vice versa, and you can easily watch the lens make its adjustment.
Quiet focusing is normal for HSM systems and this one again meets that expectation, though it is very slightly louder than some recently-introduced lenses.

Angles of view this wide typically result in lots of depth of field and AF systems are not very stressed to keep a subject within that depth of field.
Regardless, AF accuracy from this lens has been quite good for me and focus calibration can be adjusted (in detail) using the Sigma Dock (more later).
As noted and demonstrated earlier in the review, focus shift is an issue and calibration via the dock will not resolve this one (though calibration for a specific aperture may be possible).

As usual for Sigma HSM implementations, internal focusing is featured and FTM (Full Time Manual) focusing is enabled.
Both are nice features commonly found on quality lenses.

The 12-24’s effective focal length changes modestly with focusing, causing subjects to change size slightly as the focus ring is turned.
The review copy of this lens requires a focus adjustment change after changing focal lengths (it is not parfocal), but depth of field can easily cover the change in many instances.

The 12-24 Art’s manual focus ring is very nice – smooth with no play and with an ideal amount of rotation for precise manual focusing even with very close subjects.
The location of this ring, positioned on the rear of the wide portion of the front of the lens, is a bit unusual.
The focus ring is somewhat narrow and inherently quite wide in diameter.
With only the rubber ribs very slightly raised above the barrel, the ring is well protected from inadvertent focus changes though quite usable.

A great trend currently being seen in lens design is shortened MFD (Minimum Focus Distance) with increased MM (Maximum Magnification) and the Sigma 12-24mm f/4 DG HSM Art Lens adds its name to this list.
The 12-24 Art’s MFD has been shortened to 9.4″ (240mm) from 11.0″ (280mm) and the MM increases modestly to 0.20x from 0.17x.
The 0.20x spec is best-available for lenses wider than 16mm, though the spec is only mediocre in the entire field of lenses.
Here is a table showing a large array of wide angle lenses:

While 0.20x is not near record setting, combined with the 12mm focal length, the lens is able to create a very strong perspective.

To reduce the MFD and thereby increase the MM, mounting an extension tube behind the lens is generally a good option.
But, not with this lens.
With a short 12mm Extension Tube II installed, this lens has a maximum focus distance just beyond the end of the non-removable hood.
Lighting within this area becomes a real problem and the corners of the frame are visibly blurry even in the viewfinder.

Summary

I had the perfect plan to get a great sample photo using the Sigma 12-24mm f/4 DG HSM Art Lens.
Photographing the Pennsylvania Capitol building during the blue hour seemed to be a great opportunity for a sure-thing quality sample image from this lens.
I picked a clear sky day and was in position well before sunset, with the camera set up and ready to go.
The sun set and the ideal moments within the blue hour came and went, but … the lights on the capitol dome were never turned on.
I gave up with about 25 minutes remaining before the capitol visiting hours were over.
I ran back around to the front of the building, went the security checkpoint and took a few more interior photos.

After closing time, I checked out some other potential opportunities before picking up the car and driving to nearby City Island to photograph the green and red
Christmas-colored lights under a bridge reflecting in the Susquehanna River.
As I was photographing these lights, I noticed that the capitol dome lights were now on. Argg.

I decided that I was this close and photographing them would not get much more convenient.
But, I didn’t want to pay another parking garage fee (I was currently in a 2-hour-free parking spot on the island).
So, I lightened my load, taking just the 12-24 Art on an EOS 5Ds R and the tripod in my other hand.
I ran/fast walked over a mile back to the capitol, took a set of photos and ran/fast-walked back.

While neither set of exterior capitol dome photos were bad, they were not what I originally envisioned and coming in below expectations is always disappointing.
Fortunately, there is digital image compositing.
On my second visit that day, I (unintentionally) selected the same focal length (20mm) and nearly identical framing as used in the first visit, resulting in two images that could be overlaid.

I captured some nice interior shots on this day and more importantly, I learned (more like confirmed what I expected) that this is a really fun lens to use.
Some product evaluations are more fun to perform than others and this one ranks high up on the list.
The Sigma’s great overall quality with the extremely wide focal lengths are what drive the fun-ness.
This is not a cheap lens, and the focus shift is a notable shortcoming, but it delivered some very nice images for me.

A 12-24mm lens is not likely to be the sole lens in a kit, but it will complement nearly all lens kits very well.
This lens will inspire creativity and provide uniqueness in your imagery.

Sigma 12-24mm F4 DG HSM Art Introduction

The Sigma 12-24mm F4 DG HSM Art is a new ultra-wide-angle zoom lens for full-frame and APS-C DSLR cameras. It offers the equivalent angle of view as an 18-36 mm lens on an APS-C system (depending on the crop factor). The Sigma 12-24mm F4 DG HSM Art has 16 elements in 11 groups and the largest aspherical glass mold (80mm diameter) in the industry and it features a rounded 9 blade diaphragm which creates an attractive blur to the out of focus areas of the image. It has a minimum focusing distance of 24cm / 9.4in and a maximum reproduction ratio of 1:4.9, silent high-speed AF performance, full-time manual focusing, dust- and splash-proof construction and Sigma’s Super Multi-Layer Coating to reduce flare and ghosting. The Sigma 12-24mm F4 DG HSM Art lens retails for £1649.99 / $1599 in the UK and the US, respectively.

Sony FE 12-24mm F4 G Introduction

The Sony FE 12-24mm F4 G is a new ultra-wide-angle zoom lens for Sony full-frame FE-mount cameras (A9/A7/A7R II/A7S). It has four aspherical elements, including one Super ED and three ED elements. The lens is dust- and moisture-resistant and has a minimum focusing distance of 28cm with a maximum magnification of 0.14x. It has a 7 blade diaphragm which creates an attractive blur to the out-of-focus areas of the image, an internal focusing mechanism means the lens barrel doesn’t move, and there’s a Nano AR coating to help minimise flare. The Sony FE 12-24mm F4 G lens is available for around £1700 / $1700 in the UK and the US, respectively.

Sigma Global Vision and the USB Dock

Sigma’s Global Vision lenses get a classification of «A», «C» or «S», representing a primary Sigma-intended use of «Artistic», «Contemporary» and «Sports».
A full description of these categories can be found in the Sigma 35mm f/1.4 Art Lens press release.

Sigma has been introducing some very nice lenses in the Global Vision series, but I have never been a fan of the narrow categorization structure.
This of course is an «Art» lens and as such, gets an «A» stamped in a classy chrome circle on the lens barrel.
Don’t limit the lens’ use to its letter designation.

One |
Two |
Three |
Four

The focus calibration values were set for illustration purposes only.

Price and Value

This is a moderately expensive lens, but if compared to the closest non-Sigma alternative, the Canon 11-24, it is a bargain.

The Sigma 12-24mm f/4 DG HSM Art Lens is available in Canon (reviewed), Nikon, Sony/Minolta and Sigma mounts and qualifies for Sigma’s Mount Conversion Service in case you change your mind.
My standard disclaimer: There are potential issues with third party lenses.
Since Sigma reverse engineers (vs. licenses) manufacturer electronics and algorithms, there is always the possibility that a DSLR body might not support a (likely older) third party lens.
Usually a lens can be made compatible by the manufacturer via a firmware update, but this cannot be guaranteed.
There is also the risk of a problem that results in the lens and body manufacturers directing blame at each other.
Compatibility with the Sigma USB Dock is risk reducing as Sigma can release firmware updates for dock-compatible lenses.
Sigma USA’s 4-year warranty is superior to Canon’s standard 1 year warranty (Sigma’s international warranty is also 1 year).

The reviewed lens was sourced online/retail.

Sony FE 12-24mm f4 G SEL1224G User Reviews

10.0/10
average of 1 review(s)

Build Quality
10.0/10

Image Quality
10.0/10

Write your own review!

10 out of 10 points
and recommended
by
Echoauxgen
(1 reviews)

Min coma
min star trailing @ 30 sec.
Larger than SEL1018
No filter threads

I have used many ultra wides Voigtlander 10mm and 12mm, Rokinon 12mm and 14mm, Sony SEL1018 in full frame mode at 12mm to 18mm. When you go beyond 16mm distortion is going to be there. Interior shots are a skill to adapt to and exterior a clear foreground with included background another skill in composition. I use the A7S to do mainly Astro Milky Way capture where an ultra wide can save you from doing a panoramic to get rid of bad stars on the sides and only use center parts when merged. The Rokinon’s have a bad problem with star trailing in upper right and some left and some coma (dove stars) that everyone excepts at the f/2.8 but putting at f/4 or f/5.6 can reduce. The Voigtlander’s small and most perfect at 10mm f/5.6 you get a 50 sec. shot to make up for the f/5.6 reduced light. The SEL1018 is just a smaller but softer on edges and some vignetting corners when doing dark captures and coma.
This lens after giving a workout on several nights before a new moon as well as a full clear Milky Way night with about 50 shots in the dark and lit places was superb as the Voigtlander’s. There is no worry about having just f/4 when using with the A7S because it gathers more light and to correct of coma and star trailing you have to increase f/ anyway. Any lens but ultra wides especially the camera has to be level and pointed at the center of the subject.
This lens an image zoomed to 400% in Capture One coma was min. as well as star trailing at just the 30 sec wall most do, 42 sec if in bulb. Stars in each corner were pin point as the center with no softness at the sides, Subject in foreground (a boat dock) was sharp/clear and lights/houses across the water were sharp even at f/4.
The Voigtlander 12mm and SEL1018 have screw on filters threads for this lens NiSi has a 150mmx150mm filter holder (fits perfect) so you can use the NiSi Clear night light filter or Lonelyspeck Purenight filter (for ground light and MW color/sharpness. For anything wider than 16mm a Polarizer gives uneven sky color!
Used with the A7RM2 for day shots/sunsets with awesome sharpness also handheld with IS on or tripod IS off. With some wides you get drop off up close on sides BUT not this lens.

reviewed August 15th, 2017
(purchased for $1,698)

Ease of Use

Weighing in at 1150g and measuring 13cms in length, the Sigma 12-24mm F4 DG HSM Art is a very big lens indeed, almost identical to the Canon EF 11-24mm f/4L USM. While you can use it on a smaller APS-C body for an 18-36mm equivalent angle of view, it won’t balance very well at all. As demonstrated by the images below, it’s a much better match for a professional-grade, full-frame camera like the Canon EOS 5DS R, and even then you’d probably want to fit a battery grip when using it hand-held.

The Sigma 12-24mm F4 DG HSM Art lens mounted on a Canon EOS 5DS R

The Sigma 12-24mm F4 DG HSM Art lens mounted on a Canon EOS 5DS R

The Sigma 12-24mm F4 DG HSM Art lens mounted on a Canon EOS 5DS R

The Sigma 12-24mm F4 DG HSM Art lens alongside a Canon EOS 5DS R

Build quality is excellent. The lens has a plastic shell with a mixture of metallic parts and a new compound material, TSC (Thermally Stable Composite), used inside. It also incorporates a brass bayonet mount that’s supposed to be more durable. The optical elements are made of high-grade glass. The focus ring is rather narrow, although it is at least ridged for easier grip. The lens also features a distance scale.

Side of the Sigma 12-24mm F4 DG HSM Art lens

Side of the Sigma 12-24mm F4 DG HSM Art lens

In terms of features, the Sigma 12-24mm F4 DG HSM Art offers all the basics that you need, and it’s usefully weather-sealed too thanks to its dust- and splash-proof construction. The main exception is the lack of built-in Vibration Reduction.

Front of the Sigma 12-24mm F4 DG HSM Art lens

Rear of the Sigma 12-24mm F4 DG HSM Art lens

Front of the Sigma 12-24mm F4 DG HSM Art lens

Rear of the Sigma 12-24mm F4 DG HSM Art lens

Focusing is usefully internal and manual focusing is possible when set via the Focus switch on the lens barrel. Full-time manual focus override is also available at any time simply by rotating the focus ring. A clear distance scale in both feet and meters runs from the closest focusing distance of 0.24m / 0.79 ft to infinity.

The Sigma 12-24mm F4 DG HSM Art lens in-hand

The Sigma 12-24mm F4 DG HSM Art ships with a good quality soft case, a fixed plastic petal-shaped lens hood and a large round lens cap. Given the cost of the lens, we’d have liked to have seen a hard case included. Note that this lens doesn’t accept standard screw-on circular filters due to its large, bulbous front element.

Focal Range

At the 12mm focal length the angle of view is 122 degrees, and at the 24mm focal length it’s 84.1 degrees.

 Field of view at 12mm

Field of view at 24mm

Focusing

The Sigma 12-24mm F4 DG HSM Art lens has a rather narrow focus ring. There are hard stops at both ends of the range, though, making it easier to set focus at infinity.

When it comes to auto-focusing, the Sigma 12-24mm F4 DG HSM Art zoom is a quick performer, taking about 0.15 seconds to lock onto the subject when mounted on the Canon EOS 5DS R that we tested it with.

We didn’t experience much «hunting», either in good or bad light, with the lens accurately focusing almost all of the time. It’s also a very quiet performer, thanks to the built-in HSM (Hyper Sonic Motor), which makes this lens well-suited to video recording.

Chromatic Aberrations

Chromatic aberrations, typically seen as purple or blue fringes along contrasty edges, is quite well-controlled but can be detected in some shots, as shown below.

Light Fall-off

With the lens set to its maximum aperture of f/4, there is some light fall-off in the corners. Stopping-down to f/8 virtually eliminates this.

Light fall-off at 12mm

Light fall-off at 24mm

Macro

The Sigma 12-24mm F4 DG HSM Art isn’t claimed to be a macro lens, with a minimum focusing distance of 24cm / 9.4in. and a maximum magnification ratio of 1:4.9. The following example demonstrates how close you can get to your subject.

Close-up performance

Bokeh

Bokeh is a word used for the out-of-focus areas of a photograph, and is usually described in qualitative terms, such as smooth / creamy / harsh etc. In the Sigma 12-24mm F4 DG HSM Art lens, Sigma have employed an iris diaphragm with nine rounded blades, which has resulted in nice bokeh in our view. We do realise, however, that bokeh evaluation is subjective, so we’ve included several 100% crops for your perusal.

Sharpness

In order to show you how sharp this lens is, we are providing 100% crops on the following pages.

1. Ease of Use
2. Sharpness: 12mm

3. 18mm

4. 24mm

1. Sample Images
2. Lens Specs
3. Rating & Conclusion

1. Main Rivals
2. Review Roundup

1. Ease of Use
2. Sharpness: 12mm

3. 18mm

4. 24mm

5. Sample Images
6. Lens Specs
7. Rating & Conclusion
8. Main Rivals
9. Review Roundup

Build Quality Features

With the Global Vision series, Sigma introduced a modern, classy-looking, tightly-dimensioned, high-quality design for their lenses.
These lenses feel as great as they look, increasing their fun-to-use factor.
While the Sigma 12-24mm f/4 DG HSM Art Lens, with the large convex objective lens, has a somewhat unique shape, it definitely looks like a member of the Global Vision family.

MFD |
∞
   MFD |
∞
   Rotated
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While this lens does not change external dimensions when zoomed, the objective lens does move in/out within the permanently affixed hood.
The zoom ring is easy to find and, with the focus ring riding on the broad part of the lens, it is not easy to confuse the two rings.
The only other moving exterior part is the manual/auto focus switch nicely positioned on a slightly raised switchbank.
As standard with Global Vision lenses, the back of the switch shows white when in the auto position.

This lens has some weather sealing, including a rear gasket seal as seen below.

Increase the aperture by 2/3 to a full stop and the lens elements are going to be significantly larger.
Lens elements are not light, so increasing the size of the lens elements is going to be noticed on the scales.
And, as you would expect, the 12-24 Art weighs in at a noticeably-heavier weight than the 12-24 II, though it does not quite catch the Canon 11-24.

For many more comparisons, review the complete Sigma 12-24mm f/4 DG HSM Art Lens Specifications using the site’s Lens Spec tool.

The weight of this lens is noticeable when carried for long periods of time, but not burdensomely so.
The size of this lens has also increased from the II, but it remains in line with other popular lenses.

Positioned above from left to right are the following lenses:

Canon EF 8-15mm f/4 L USM Fisheye LensNikon 14-24mm f/2.8G AF-S Lens
Sigma 12-24mm f/4 DG HSM Art LensCanon EF 11-24mm f/4L USM LensTamron 15-30mm f/2.8 Di VC USD Lens

Use the site’s product image comparison tool to visually compare the Sigma 12-24mm f/4 DG HSM Art Lens to other lenses.

As already noted, this lens is not compatible with standard threaded front filters and no provision is made for use of a rear drop-in gel filter.
Those wanting to use circular polarizer and neutral density filters
will need to make use of a third party filter holder and very large filters.

Commonly provided with lenses having integrated hoods is a lens cap that also covers the sides of the hood and that lens cap style is provided with the 12-24 Art lens.
This cap uses a friction fit via a thin ring of flocking-like material inside the hood.
While staying attached is problematic for some of these caps, this one has been holding on nicely.

The Sigma 12-24mm f/4 DG HSM Art Lens arrives in a nice zippered padded nylon case with a shoulder strap, though without a belt loop.

Max Aperture

Wide apertures are often desirable for creating shallow depth of field, but what wide angles are not best at is creating diffusely-blurred backgrounds.
The out-of-focus details in the background are not enlarged enough for a strong blur to be created by the ultra-wide angles of view.

Wide apertures are also desireable for the light they allow to reach the sensor, permitting shorter shutter speeds and/or lower ISO settings, but wide angles tend to render subjects small in the frame.
Small in the frame means that subjects do not cross sensor pixels as fast, meaning that longer shutter speeds may be adequate for capturing sharp images, negating some of the need for wider apertures.

The f/4 max aperture is moderately wide.
However, the f/4 max aperture, available over the entire focal length range, is a nice feature upgrade from Sigma’s last 12-24mm lens.
That was an f/4.5-5.6 lens, but the f/4.5 aperture was only available at 12mm, so it was mostly an f/5.0-5.6 lens.
I like that the Art lens’ has a wider aperture and especially like that wide open exposure settings can be maintained over the full focal length range.

It would have been great to see Sigma take this lens out to f/2.8 as this focal length range is great for night sky photography.
But, this already somewhat heavy lens would have taken on considerably more weight and I’m sure there would have been a significant price penalty in addition.
Otherwise, I do not encounter many situations where an f/4 aperture is inadequate in this focal length range (and nightscapes can be captured at f/4 at ultra-wide angles).

Ease of Use

Weighing in at 560 grams and measuring 87 x 117.4 mm, the metal-bodied Sony FE 12-24mm F4 G feels very well-constructed. It’s overall size and weight makes it feel well-balanced on the Sony A7R II body that we tested it with, as shown in the photos below.

The Sony FE 12-24mm F4 G lens mounted on a Sony A7R II

The Sony FE 12-24mm F4 G lens mounted on a Sony A7R II

The Sony FE 12-24mm F4 G lens mounted on a Sony A7R II

The Sony FE 12-24mm F4 G lens alongside a Sony A7R II

The Sony FE 12-24mm F4 G has a sealed dust and moisture resistant design. It does not feature built-in Optical SteadyShot image stabilisation.

The wide and ridged zoom ring and the narrower manual focus ring are the main external controls of note. Manual focusing is possible via the textured focus ring when set on the specific camera body. The lens utilizes one DDSSM (Direct Drive Super Sonic Wave Motor) to produce quiet and smooth focusing, making it well-suited to shooting both stills and video.

There is also a customisable focus hold button and a lens hood release button.

Side of the Sony FE 12-24mm F4 G lens

Front of the Sony FE 12-24mm F4 G lens

Rear of the Sony FE 12-24mm F4 G lens

The Sony FE 12-24mm F4 G lens has quite a wide focus ring. There are no hard stops at either end of the range, making it a little more difficult to set focus at infinity.

When it comes to auto-focusing, the Sony FE 12-24mm F4 G zoom is a quiet and quick performer on the Sony A7R II that we tested it with, taking about 0.15 seconds to lock onto the subject.

We didn’t experience much «hunting», either in good or bad light, with the lens accurately focusing almost all of the time, and it’s also a quiet performer making it ideal for movie shooting.

Side of the Sony FE 12-24mm F4 G lens

Side of the Sony FE 12-24mm F4 G lens

The Sony FE 12-24mm F4 G lens in-hand

The Sony FE 12-24mm F4 G lens has a metal lens mount. It does not accept filters because of the integrated plastic petal-shaped lens hood which cannot be detached. It is supplied with a soft case and a large lens cap which slips over the hood.

Focal Range

At the 12mm focal length the angle of view is 99 degrees.

 Field of view at 12mm

At the 24mm focal length the angle of view is 61 degrees.

 Field of view at 24mm

Chromatic Aberrations

Chromatic aberrations, typically seen as blue or purple fringes along contrasty edges, were almost completely absent from our test shots. The examples below show the worst-case scenario.

Light Fall-off and Distortion

With the Sony FE 12-24mm F4 G lens set to its maximum aperture of f/4, there is some obvious light fall-off in the corners, requiring you to stop down by at least 3 f-stops to completely prevent it. There’s some barrel distortion evident at 12mm, and at 24mm there’s just a little pin-cushioning too.

Light fall-off at 12mm

Light fall-off at 24mm

Macro

The Sony FE 12-24mm F4 G isn’t claimed to be a macro lens, offering a minimum focusing distance of 28cm at 12mm, with a maximum magnification of 0.14x. The following example demonstrates how close you can get to your subject.

Close-up performance

Bokeh

Bokeh is a word used for the out-of-focus areas of a photograph, and is usually described in qualitative terms, such as smooth / creamy / harsh etc. In the FE 12-24mm F4 G lens, Sony employed an iris diaphragm with 7 rounded aperture blades, which has resulted in fairly appealing bokeh in our view. We do realise, however, that bokeh evaluation is subjective, so we’ve included several 100% crops for your perusal.

Sharpness

In order to show you how sharp this lens is, we are providing 100% crops on the following pages.

1. Ease of Use
2. Sharpness: 12mm

3. 18mm

4. 24mm

1. Sample Images
2. Lens Specs
3. Rating & Conclusion

1. Main Rivals
2. Review Roundup

1. Ease of Use
2. Sharpness: 12mm

3. 18mm

4. 24mm

5. Sample Images
6. Lens Specs
7. Rating & Conclusion
8. Main Rivals
9. Review Roundup