Sigma 210101 18-35mm F1.8 DC HSM Lens for Canon - Black

Product Information

The 18-35mm is remarkably sharp even wide open at F1.8, and in the wider half of its range (18-24mm), there's no measurable increase on stopping down (i.e. the lens is effectively diffraction limited). At the longer end (28-35mm) there's a slight improvement in sharpness on stopping down to F4, but in practice it's unlikely to be especially noticeable. For an F1.8 zoom, this is little short of astonishing. A consequence of all of this is that in principle you'll get the very best results at large apertures by focusing and shooting in live view. This has its own pitfalls though - for example when focusing manually with Nikon's DX SLRs you have to remember to set the aperture to F1.8 before entering live view, as they're incapable of adjusting the lens's diaphragm during viewing. If you initiate live view at a smaller aperture, then you risk getting misfocused images. Meanwhile Canon users may have to set the aperture to F1.8 and press the depth of field preview button to force the lens wide open for accurate manual focusing, when shooting in bright light. Autofocus microadjustment This shot, taken at ISO 1000 and F2 would have required a higher ISO with any other zoom lens. Photo by Richard Butler As part of the Art line within Sigma's Global Vision series, this lens is designed to achieve truly notable optical performance and is ideally suited for creative and artistic applications.

Sigma 18-35mm f/1.8 ART review: best Canon R5 video lens? Sigma 18-35mm f/1.8 ART review: best Canon R5 video lens?

Overall the 18-35mm F1.8 is a really intriguing product, and we applaud Sigma for pushing the boundaries of lens design ahead of the more conservative camera manufacturers. But can an F1.8 zoom really deliver good results? Let's find out. Headline features Convenient handling is achieved by incorporating internal focusing and zooming which prevents any change in the length of the lens when focusing and zooming. It is possible to use a specialist filter, such as a Circular Polarizer, as the front part of the lens does not rotate. Sigma's choice of F1.8 as maximum aperture isn't a coincidence; it means that the lens will offer the same control over depth of field as an F2.8 zoom does on full frame. What's more, combined with an APS-C sensor, the system will also offer effectively the same light-gathering capability as an F2.8 lens on full frame. By this we mean that it will be able to project an image that's just over twice as bright onto a sensor that's slightly less than half the area, meaning the same total amount of light is used to capture the image. This is important as it's a major determinant of image quality. Essentially it means that APS-C shooters will be able to use lower ISOs when shooting wide open in low light and get similar levels of image noise, substantially negating one of the key advantages of switching to full frame.We understand this can sometimes be difficult with work commitments, but we will do our best to accommodateyour needs.

Sigma 18-35mm F1.8 DC HSM A Canon - DXOMARK

These lenses can be compared in several different ways, but its clear that regardless of whether we look at them them both tested on the same camera body, or at how the Sigma on APS-C compares to the Tamron on full frame, the 18-35mm easily holds its own in these studio tests. Compared to Canon EF-S 17-55mm f/2.8 IS USM The other take-home message here is that, while our copy of the lens showed a tendency towards focusing in front of subject (and therefore required positive microadjust values), the correction needed at each setting was different. So using a global in-camera microadjust value would necessarily be a compromise - setting a value to correct any given focal length and subject distance could throw off the focus at other settings. We observed this in practice using the Canon EOS 7D's microadjust feature - it could only be set to give optimal focusing at one given focal length and subject distance. Are we looking too closely?And that’s the confusing thing about “4K Crop” video on the R5, for when an APS-C lens like the Sigma is attached, it may appear the R5 is shooting in regular 4K because 4K HQ mode is disabled. But it’s not. Behind the scenes, with Movie Cropping enabled, the R5 is oversampling 5.1K when shooting 4K. Every time I review a Sigma lens I will be closely looking at the AF (autofocus) performance. I’ve rarely had a problem with HSM motors when it comes to sound or speed (they are amongst the quietest focusing lenses that I’ve encountered and generally quite fast), but I have major concerns when it comes to AF accuracy and consistency. The Sigma 150-600mm Sport was the first Sigma lens that I walked away completely satisfied from when it came to its AF performance. I’m afraid the 18-35mm ART didn’t impress out of the box. My review body is a Canon EOS 70D, and trying to use my typical AFMA program ( Reikan FoCal) produced such variation that an automatic calibration simply didn’t work (the program gave up). I did a semi-automatic calibration using my own eyes, and discovered why. Just when I thought I had a value zeroed in, the results would jump around. The focus peak looked like a yo-yo. I’ve never had such a difficult time calibrating a lens before. Just like CA and vignetting, distortion is nicely controlled, although not eliminated altogether. We see a bit of barrel distortion at focal lengths wider than 24mm, but less than we might normally expect from a zoom. At 18mm, there is about 0.5% of barrel distortion in the corners while only 0.3% for the average across the frame. At 24mm, the average distortion approaches 0%, yet we start to see a bit of pincushion distortion starting to appear in the corners. Oddly, as focal length increases from 24-35mm, the average shows a very slight increase in overall barrel distortion, while the corners experience a noticeable increase in pincushion. However, the pincushion distortion at 35mm is not extreme – we measured less than -0.5%.

Sigma 18-35mm f/1,8 DC HSM Art Review - Lensora Sigma 18-35mm f/1,8 DC HSM Art Review - Lensora

This procedure certainly improved overall focus accuracy when shooting at the distances used for microadjustment. However these are fixed by the software, and there's no option to specifically correct any distance between infinity and 0.5m. Unfortunately though, the vast majority of subjects end up somewhere in between, and we found that the lens still had some problems with focus accuracy even when fully programmed as above. Knowing this, we'd probably configure the 'Infinity' position with a bias towards getting the most accurate focus at closer subject distances.Even as slightly jaded camera reviewers, we were pretty stunned when Sigma told us it was going to make an 18-35mm F1.8 zoom. The company has shown real ambition, particularly in recent years, to cement an increased reputation for itself - its 50mm F1.4, 85mm F1.4 and 35mm F1.4 lenses, for instance, have proved to be really impressive, with no need for caveats about them being from a third-party lens maker. But a constant F1.8 zoom? Was that even possible? On smaller, lighter entry-level SLRs such as the Canon EOS 650D, the overall balance becomes more front-heavy, meaning you'll often find yourself supporting the camera by cradling the lens itself. Frankly, these models tend not to have hand-grips that are comfortable to hold for long periods anyway, so this encouragement to support the lens is no bad thing. Size compared Vignetting is remarkably low for such a fast lens, reaching just 1.3 stops wide open at all focal lengths. It also essentially disappears by F2.8. Overall it's unlikely ever to be problematic in real-world use. Oversampling 5.1K to 4K is apparently less taxing on the camera than 8K to 4K, so the R5 does not heat up or require periodic cool downs as it does when shooting “4K HQ” video. The only limitation with “4K Crop” then is the R5’s 30 minute record time limit, which is standard in all their non-cinema cameras. Downsides of the Sigma 18-35mm f/1.8 Here you can also see the 'Made in Japan' label - not something you'll find on all lenses any more.