Sigma 18-50mm F2.8 DC DN | C for Sony E

Product Information

And now for the Sigma 18-50 at 50mm where it delivers a 75mm equivalent field of view that’s great for portraits as I’ll show you in a moment. In my tests the Sony 16-50 matched this view at the long-end as its specs suggest. The 24-200DXVR is stronger on the long end, sharper in the center, and can be used on an FX when/if you upgrade/rent. But while 20fps with continuous AF may be enough to seal the deal for many photographers, the DL series also enjoys other unique benefits. Rather than launch with one product, Nikon has gone for three models, differentiated mostly by their lens ranges. Indeed the DL 18-50 and DL 24-85 are identical other than their zooms: 18-50mm f1.8-2.8 and 24-85mm f1.8-2.8. In a World where we’ve become used to DSLR kit zooms offering 18-50mm ranges, it’s easy to dismiss the first DL model as having an average range, but look again because these figures have already been converted into equivalent ranges. So the DL 18-50 actually boasts by far the widest coverage of any fixed lens compact – much wider than the typical 24mm of rivals – and still couples it with a bright focal ratio and the ability to zoom-into 50mm for standard coverage, still with a respectable f2.8 focal ratio. For me, this is the most compelling of the three models.

One aspect we never want to be compromised is the image quality produced by a lens, especially a most frequently used lens. This lens has a small, plastic-ribbed focus ring that has the same diameter as the lens barrel — is it not especially easy to find.As is normal for standard zoom lenses, the 18-50 DC DN extends when zoomed to its longest focal length, but the full extension is only 0.86" (21.9mm). The advantages of a smaller image circle are reduced cost, decreased size, and a lower price, and the Sigma 18-50mm F2.8 DC DN Contemporary Lens embodies those attributes while still providing a zoom range, wide aperture, and impressive image quality. Extension tubes are hollow lens barrels that shift a lens farther from the camera, allowing shorter focusing distances at the expense of long-distance focusing.

Pop the Sigma on the left with the Sony on the right, both at 50mm, and you’ll immediately see the difference between a lens that can open to f2.8 on the left versus one that’s limited to f5.6 on the right. To be fair, the Sony’s actually fairly sharp on the focused areas, but there’s unsurprisingly little blurring behind me to speak of. Just out of interest, I’ll switch the Sigma image on the left for one with its aperture closed to f5.6 to match the Sony on the right to compare their rendering styles, and in this instance I’d say the Sony is a fraction less busy, but as you’ll see in the next test the Sigma takes a lead. I also don't think it is a dud because the wobble is probably due to the extremely ambitious retractable design. I have not seen many interchangable lens designs that are so aggressively retractable. Nikon's retractable kit is barely retractable compared to the Pentax which has what looks like a double-cam retractable mechanism that extends very aggressively from its rather compact retracted form. It probably just isn't physically possible to make a cheap, heavily collapsible/retractable, plastic kit lens that doesn't have wobble. The optical formula is comprised of 13 elements in 10 groups, including 1 Special Low Dispersion (SLD) lens to reduce chromatic aberrations and color fringing and 3 aspherical lenses to limit distortion and spherical aberrations. And, the overall size and weight of the Sigma 18-50mm f/2.8 EX DC Lens is ideal for the cameras it is designed for.The phrase "... the use of in-camera aberration correction further eliminates optical imperfections such as distortion ..." [Sigma] warns of impending geometric distortion. Somewhat unusual is that this lens is capable of a significantly higher reproduction ratio at 18mm than 50mm. In use, we found the focusing system to be quiet, fast and reliable with the lens mounted on a Sony A6000 camera. Ok to compare their quality I’ve angled my landscape view so that details run into the corners, starting here with the Sigma 18-50 at 18mm f2.8. Taking a close look at the middle shows good detail as you’d expect, and there’s little benefit to closing the aperture other than a minor boost in contrast. Heading out into the corner, still at f2.8, you’ll see the Sigma maintaining the sharpness, and again there’s only small benefits to closing the aperture, like a mild boost in contrast and a small reduction in fringing. I’d be happy shooting wide-open where necessary or desired for a shallow depth of field, but for the maximum quality across the frame, try f5.6 to f8.

The rear portion of the hood is rubberized to, along with the mold-ribbed ring, facilitate installation and removal. Ok so now for the rendering of bokeh balls at close range, again starting with the Sigma 18-50mm at 50mm f2.8 and focused close to its minimum distance. At the maximum f2.8 aperture, the Sigma lens is delivering fairly large bokeh balls with a little outlining and some mild textures within – not surprising for a zoom of this size, but still a step-up from budget models. And now closed to f4, then f5.6 and finally to f8.The Sigma's 18-50's minimum focus distance is 11" (0.28m) and provides a reasonable .2x magnification factor. Most will appreciate this lens's constant max aperture, enabling f/2.8 throughout the focal length range. Not impressed with the Nikon 18-55 VR II retractable or Sony 16-50 either. So far the best compact kit lenses are the ones for MFT.

If I leave it alone and do not mind it, yes I agree I can get good pictures still particularly in the center. But knowing that a slightly more 'refined' lens would be capable of quite a bit more in IQ is unfortunate.Cityscapes, countrysides, flowers, medium and large products, and much more are in this lens's capabilities list. A relatively common lens aberration is axial (longitudinal, bokeh) CA, which causes non-coinciding focal planes of the various wavelengths of light. Also the specs say the macro capability is not as good as previous versions but I was somewhat impressed...maybe I just didn't test out the previous version enough in this regard. I shot some more in the morning but haven't had a chance to review on my computer but based on what I can see from LCD chimping so far-