Sigma 30mm f1.4 Contemporary DC DN Lens for Sony E with...

Most Helpful Review

"If possible, I would have given this lens 7/10 but decided to err on the lower side (3 stars instead of 4) for the reasons below.I have a Sony A5100 Camera and a number of prime lenses (including the Sigma 30mm f/2.8) but wanted a fast lens for indoor/low light. Given the excellent reviews I felt this lens would suit my needs and to be fair, to an extent it does, however…I believe these reviews are to help prospective buyers make a decision and therefore, I think there are a couple of things to be aware of.If you check the many forums and reviews for this lens you will find that whilst the majority of people have no problems at all, a small number have reported focus issues at f2 and a few have reported issues at f4. My copy suffers from the latter (f4). It’s very specific to this aperture setting and simply going one stop either way resolves the issue. Also, it only seems to be a problem when using AF-S, if I switch to AF-C it’s fine. It is also okay when using manual focusing (which I rarely do).Over the weekend I took a variety of comparison shots (this lens vs 30mm f/2.8) at f2.8, f4, f5.6 and f8. It was a bright day, all the photos were taken within seconds of each other and I used a tripod for consistency. I used AF-C at f4 with this lens to get around my f4 issue, all other photos were taken in AF-S.All the photos were very similar, with the 30mm f/1.4 generally producing very slightly ‘warmer’ results. However, I have to admit to being a pixel-peeper and, when cropped, the 30mm f/2.8 was always slightly sharper (this was hardly noticeable when viewing the full image on a computer screen).Wide open this lens is capable of some very sharp shots and I’ve managed to get some great photos of the grand kids (who never stay still) indoors at f1.4 through to f2.At this point I should say that both Camera and Lens have the latest firmware updates, I don’t shoot video and the photos are OOC JPEG’s.In conclusion. If you only shoot outdoors and you don’t need the subject separation you can get with a fast lens, go for the 30mm f/2.8, it’s smaller, lighter, cheaper and IMO slightly sharper.If you do go for the 30mm f/1.4 check for the f2 / f4 focus issue as soon as possible. If it’s there and you don’t feel you can live with it, Amazon are usually excellent when it comes to returns and (from what I’ve read) you would be very unfortunate to get two bad copies.Based on the reviews I’d read previously I was hoping this lens would replace the 30mm f/2.8 as my ‘all-rounder’, the lens that stayed on the camera most of the time, but for me, it doesn’t. I’ll keep it for its excellent indoor/low light capabilities but, if I’m going out on a nice day, I’m afraid this lens will be left at home…"