You need the focal length that is going to allow proper framing and proper perspective for your subjects. This lens has barrel distortion at 18mm, but it performs better than many similar lenses by showing only a modest amount. The ribbed rubber rings grip well, but have sharp ridges and are much less comfortable than pro lenses. I've had the 18-35 mounted to my 60D and available for immediate use since it arrived over two weeks ago. At 18mm full-aperture sharpness is excellent from corner to corner, though sharpness in the outer field drops slightly through the zoom range to 35mm. For most focal lengths and apertures, though the sharpness differs by 5% or less across the frame.

Distortion, lateral chromatic aberration, even vignetting which appears softly gradated, are all very well corrected for a lens like this. At 1.8TStops, transmission is excellent – this really is an f/1.8 lens and will likely appeal to filmmakers as much as still photographers. Surprisingly given its price, the Sigma 18-35mm F1.8 DC HSM ships with a good quality soft case and also a plastic petal-shaped lens hood. It accepts 72mm filters. As good as the Sigma 18-35mm f/1.8 may be for video on the R5, it does come with a few downsides to be aware of. Size and weight 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.

Video Autofocus

As usual, the barrel distortion is corrected as the focal length increases until essentially being gone at around 22mm. While I'm loving what Sigma is doing with their lenses right now, I'm not yet a fan of limiting the usefulness of a lens to one of these categories 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. Based on these new lines, we have developed special software (SIGMA Optimization Pro) that can update the lens firmware and adjust parameters such as focus.

Sigma uses crappy caps. Leave them in the box for resale, and buy the real Nikon or Canon caps to use with this lens instead. Coma ( saggital coma flare) often causes weird smeared blobs to appear around bright points of light in the corners of fast or wide lenses at large apertures. In lenses that have it, coma goes away as stopped down. Sigma also clarifies that any DC lenses where the image circle is made to match APS-C sensors is used, the EOS R won't automatically switch to its built-in 1.6x crop shooting mode, meaning it will have to be set manually. A future firmware update, expected to be 'announced at a later date,' will make this switch automatic and add support for the EOS R's Scene Intelligent Auto mode. Unlike a prime lens with a single focal length, the Sigma is variable. You may zoom in-and-out without physically moving your camera setup. This offers greater flexibility, speed and creative control when composing a shot — especially when mounted on a tripod. I have not tested this on Canon, which would not be able to correct it without a lens profile, which does not exist.There is also the risk of a problem that results in the lens and body manufacturers directing blame at each other. Full Frame Cameras Canon EOS-R Full Frame Cameras Nikon Z Full Frame Cameras Full Frame L Mount Cameras Sony Full Frame Cameras Canon EOS DSLR Full Frame Cameras Nikon DSLR Full Frame Cameras Vlogging Cameras Despite its limitations when shooting stills, the Sigma 18-35mm f/1.8 is surprisingly great for video on the R5. Here’s why. Large f/1.8 aperture Features a minimum focusing distance of 28cm and a maximum magnification ratio of 1:4.3 making this lens ideal for close-ups

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 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. The lens doesn't change in length when zooming from 18mm to 35mm. In this set of evaluations, we’ve compared the Sigma zoom with the highest performing full-frame primes of the same focal lengths – 18mm, 24mm and 35mm. While it might seem a little unusual, the lenses (all high speed models) reflect the state of the art in that format and when mounted on an APS-C DSLR offer the same angle of view (at each focal length) as the Sigma. With a Sigma Global Vision lens, determining the answer to this question is very easy – just prefix a "2" to the three-digit number engraved near the lens mount. While landscape photography does not so-frequently need the f/1.8 aperture advantage this lens holds, the right weather conditionsThe Sigma 18-35mm f/1.8 DC HSM Art Lens' focal length range covers only a subset of my recommended range – equating to a 28.8-56mm angle of view on a full frame camera.