However the Sigma has handled this very well, without any obvious impact on overall contrast. Here the sun is directly impinging on the front element meaning that the hood can't help at all traditionally-designed 50mm F1.4s would probably show extreme veiling flare across the image.

The second shot illustrates a tricky situation shooting directly into the light, using a relatively large aperture (F2). But there's impressively little effect on shadow detail and contrast. There's a little radial streaking from the light source, with a few coloured spots across the diagonal from the sun. In the first example (below left) we've deliberately placed the sun within the frame and stopped right down to F11, which makes any flare patterns resolved and distinct. As usual you'll get best results using the hood by default (and it'll also help protect the front element). However in our experience the Sigma 50mm F1.4 is impressively resistant to flare, and quite obviously better than older-design 50mm F1.4s. It's not unusual for fast primes to struggle with flare when shooting into the light - all that glass means there's plenty of surface area for internal reflections. We'd probably apply a little perspective correction to this particular shot to correct the converging verticals, and the lens's impressive cross-frame sharpness means that the image file holds up to this manipulation without any trouble at all ( click here to see a geometrically-corrected version of this image).

The example above illustrates the 50mm's near-perfect correction - the roof line has been rendered as close to perfectly straight as you're likely to see. And while this degree of optical correction often comes with some penalty in corner sharpness, this isn't really the case here - the shot below is pretty much critically sharp right across the frame at F4. These days distortion is extremely easy to correct in post-processing, of course, but it's still nice to see a lens that makes this utterly unnecessary. The studio tests indicate that the Sigma shows very low distortion, and this makes it extremely well suited to shooting geometric compositions such as architecture. Which you prefer is very much a personal choice there's no inherently right or wrong answer here. The rollover above compares an image shot at F1.4 on the Canon EOS 6D with a version that's had the worst of the vignetting corrected using Photoshop's generic lens correction tools. In practice you'll probably only really notice vignetting with images that have even-toned areas covering much of the frame - typically this means blue skies. This is a very impressive result, even by the standards of 50mm F1.4 lenses (which are generally well-corrected for lateral CA). The first is looking at lateral CA, and reveals just the tiniest amount of blue/yellow fringing along high-contrast edges in the extreme corners however you have to look really closely to see it. The examples below are effectively torture-tests for the two types of CA. The overall result is very impressive - there's scarcely anything to worry about here at all. colour fringing around out-of-focus elements at large apertures). Our real-world shooting confirms this, and shows that Sigma has also done an impressive job of minimizing longitudinal CA too ( i.e. Our studio tests reveal that the 50mm F1.4 exhibits exceptionally low lateral chromatic aberration, with essentially no colour fringing towards the corners of the frame. This becomes more marked at F16, but this aperture should still be eminently usable when extended depth of field is required. There's barely any visible change from F2.8 through to F8, then just the slightest hint of diffraction softening at F11. However it essentially catches up with the centre on stopping down to F2.8. The corner crop isn't quite so good, but is still hugely impressive for a 50mm F1.4 prime. What you should be able to see here is that central sharpness is already excellent wide open, and only slightly improves on stopping down.

Sigma lens 50mm