Build and Handling
The Sigma 17-50mm f/2.8 camera lens has an all-black plastic build, including the 77mm lens filter thread, albeit with the exception of the lens mount, which is made of steel. In addition, there are rubber coatings at different parts of the lens for good handling and traction. The aperture on this lens is made up of seven curved blades that work well enough for different depths of field, especially bokeh images.
There are two switches on the lens. One of the buttons is to control the image stabilization feature. The other button is for switching between autofocus and manual focus. The focus ring on this lens is about a third of an inch. It consists of a nice rubber coating that is slightly elevated for easy turning.
The handling of the focus ring is smooth and just has enough resistance so it won’t be too loose. The focusing throw is just around 45 degrees, which is somewhat inconvenient, especially during video shoots. Also, a focus distance marking is provided atop the lens. In addition, this lens uses an internal focus mechanism; no part of the lens actually extends during focus, which is an advantage for people using filters on their lenses.
The other ring on this lens is the zoom lens. It is larger than the focus ring and actually extends the front part of the lens when turned. The ring is about ¾ of an inch and is also elevated, and rubber-coated like the focus ring. Furthermore, it has the same degree of turning as the focus ring, 45 degrees. While there is no noticeable zoom creep with this lens, this lens actually has a zoom lock at 17mm to prevent unnecessary extensions, especially when the lens is facing downwards.
Another feature of this lens is the petal-type lens hood which is a beautifully and efficiently crafted lens hood for good attenuation of unwanted light, although it loses the grip on the lens quite easily. The front and back cover on this lens also gives the lens some sort of protection.
Generally, this lens is quite handy (not too heavy), but it is smaller in size compared to the Tamron 17-50mm f/2.8 and Canon EF-S 17-55 f/2.8 lenses, making it quite easy for mobility.
Name: Sigma 17-50mm f/2.8 EX DC OS HSM
Lens Mount: Canon EF
Lens Format Coverage: APS-C
APS Equivalent: 1.5x;26 – 75mm, 1.6x;27 – 76mm
Type: Standard Zoom
Maximum Aperture: f/2.8
Minimum Aperture: f/22
Field of View Angle: 72.4 to 27.9 degrees
Minimum Focus Distance: 28cm (11”)
Maximum Magnification: 0.2x (1:5)
Optical Design: 17 elements in 13 Groups, two FLD glass elements
Diaphragm Blades: 7 (Rounded)
Focus Type: Auto and Manual
Focus Details: Internal, Hyper Sonic Motor
Zoom System: Rotational (with lock)
Image Stabilization: Yes
Dimensions (length and Diameter): 91.8mm X 83.5mm (3.6” X 3.3”)
Weight: 565 grams (19.9 ounces)
Performance-wise, this lens ranks well in the standard zoom range category for lenses in this price range. An advantage of the Sigma 17-50mm f/2.8 lens over kit lenses is the fact that it maintains the same wide aperture (f/2.8) throughout the focal length range (zoom range).
- Image Stabilization
The Optical stabilization on this lens is one of the major selling points of this lens. Some costlier lenses don’t even have this feature. The image stabilization feature works adequately during video shoots and even helps with better and sharper images, especially in low-light scenarios. The Tamron 17-50mm f/2.8 VC and Canon EF-S 17-55mm f/2.8 also have optical stabilization. However, the Tamron lens slightly edges the Sigma lens.
The Hypersonic motors (HSM), which sigma lenses are known for, is what makes this lens’ focus kick. The HSM technology in itself is awesome and Sigma products have significantly improved since making this product, but this one still leaves some qualities to be desired. The focusing in itself is awesome and fast enough even during video making.
While most recent lenses have an automatic override for manual focus over the Autofocus, the Sigma 17-50mm f/2.8 does not have this feature. You have to click a button to switch from autofocus to manual focusing. Same as the Tamron and Canon Lenses.
A disadvantage to the autofocus on this lens is that the motor is limited to just a few degrees. Therefore, using the manual focus makes it a bit unconventional compared to modern lenses. The Autofocus motor of Sigma 17-50mm f/2.8 is better than the Tamron’s while the Canon’s autofocus motor is better than the Sigma lens’ own.
The sound from the mechanical turning of the autofocus ring is pretty silent compared to the Tamron’s. While the whirring sound is not loud as to be outrightly disturbing, you can expect that an external microphone attached to a camera using this lens is going to pick up the whirring sounds.
Image and Video Quality
In terms of visual quality, this lens is impressive. The sharpness, contrast, color representation are quite on-point. It’s little wonder it is still a go-to lens today. Here are some features I checked out with the image and video quality of the Sigma 17-50mm f/2.8 EX OS HSM lens.
This lens produces adequate sharpness in the middle of the frame. The sharpness is a bit dulled at the edges though, depending on the aperture opening you are operating with. However, it is important to also say that the sharpness is maintained across the entire zoom range.
The best sharpness observed from this lens with little or zero softness at the edges are pictures taken at 17mm, f/5.6. On one hand, moving down the f.stop numbers produces higher corner softness. You get an obvious dullness at the corners of the frame at f/2.8. On the other hand, stopping down to f/11 and above tends to spread the softness across the frame due to lens diffraction at these apertures.
Moving to other focal lengths gives a slightly different image sharpness at the edges except for pictures taken at f/8, 50mm, these visuals look the sharpest of the whole bunch with a more uniform sharpness across the frame.
- Chromatic Aberrations
The chromatic aberration on this lens is not unusual for lenses in its category. Some might even come off worse. The CA is limited to a green and purple tint that is noticeable at the edges of the visual frame at the 17mm f/2.8 mark. Stopping down to f/4 shows a significant decrease in the CA. The comparable lenses, Tamron 17-50mm f/2.8 XR and Canon EF-S 17-55mmf/2.8 exhibit similar CA features but the Sigma edges both of these lenses when they are stopped down.
With a focal length range from 17mm to 50mm, this lens evidently has adequate wide-angle and a bit of telephoto capabilities since it is a lens meant for APS-C sensors. Since distortion is more apparent the farther away you get from the 50mm standard focal length, this lens exhibits some form of barrel and pincushion distortion. Although the barrel distortion is more evident.
The barrel distortion is certainly most obvious at the 17mm focal length mark while we have a less obvious pincushion distortion at the 50mm focal length. Distortion is at a minimum around the 24mm to 35mm focal length marks. The Tamron 17-55mm f/2.8 XR and Canon EF-S 17-55mm f/2.8 exhibit a worse and better distortion respectively. On a general note, the distortion from the Sigma 17-50mm f/2.8 lens is well managed and can be corrected during post-production.
- Macro Capabilities
The minimum focusing distance of just 28cm gives the Sigma 17-50mm f/2.8 lens some macro capabilities and an edge over the lens I am comparing with it. With a 0.2x zoom (1:5), it still looks a long way from being macro but the MFD of just 28cm is quite small and okay for a standard zoom lens. The macro abilities of this lens are enough for general photography although it’s far from producing quality macro photography.
As far as vignetting is concerned, the Sigma 17-50mm f/2.8 does okay, only producing a noticeable shade at 17mm and f/2.8. Shooting at other zoom ranges and aperture does not produce any significant vignetting.
The Sigma 17-50mm f/2.8 produces a rather satisfying picture and video quality. Although this lens won’t give you a cine lens quality or the quality of expensive zoom lenses, it is arguably one of the best, fairly priced, standard zoom lenses out there.
Finally, with the image and video quality of the Sigma 17-50mm f/2.8 is the Bokeh capabilities. The f/2.8 aperture decidedly gives it an advantage over kit lenses but it still manages to outperform some other lenses in the same category in terms of bokeh abilities. The impressive minimum focusing distance ensures you can achieve impressive bokeh photos and videos even at close ranges. Easily making the Sigma 17-50mm f/2.8 lens a go-to for a lot of video makers.
1.Camera: Sigma SD1
Shutter Speed: 1/125 s
Lens F-number: F/7.1
Focal length: 38mm
APS equivalent: 64mm
Photographer: Ryuichi Oshimoto
2. Camera: Sigma SD1
Shutter Speed: 1/250 s
Lens F-number: F/11.0
Focal length: 28mm
APS equivalent: 47mm
Photographer: Ryuichi Oshimoto
3. Camera: Sigma SD1
Shutter Speed: 1/25 s
Lens F-number: F/5.6
Focal length: 25mm
APS equivalent: 37mm
Photographer: Ryuichi Oshimoto
Other Important Information
The glass composition in this lens is 17 elements in 13 groups. However, the most important feature of this lens composition is the two FLD (low dispersion) glass used and the super coatings used on all the glass elements. These coatings alongside the use of low dispersion glasses help with flaring, ghosting, chromatic aberrations, and color fringing.
The Sigma 17-50mm f/2.8 lens is available for all compatible mounts but the Optical Stabilization feature is not available for some mounts e.g. Pentax crop sensor mounts. Make sure to check well for compatibility.
While the Sigma 17-50mm f/2.8 DC OS HSM is not the best standard zoom lens out there (basically due to when it was made), it does not lag behind in terms of quality at all. It matches some recent standard zoom lenses in terms of quality and offers a lot of range for photographers and videographers alike. In conclusion, the Sigma 17-50mm f/2.8 lens is the best value standard zoom lens you can get because of the cost-to-quality ratio.