Yen's Blog

Lens, Wheels, Skates, Keyboard

Sigma 50mm f/1.4 Lens for Nikon AF

I’m fond of landscape photography. However when there’s a human subject, applying the same kind of composition can come out looking too formal or posed. I’d like to achieve more of the natural, spontaneous, spur-of-the-moment feel. For that I want to have a lens that’s fast, focuses quickly and has good bokeh. A prime lens would have those qualities at a much lower price point than a telephoto lens. With that settled, I had to decide between 35, 50 and 85mm. From what I’ve read, the general opinion is that the wide-angle 35mm prime lens is good for landscape or street scenes, while 85mm is good for an intimate, close-up portrait. That leaves the 50mm, which can do either almost as well and happens to be the (only) lens on my first camera, a Canon AT-1. That it’s famously associated with Henri Cartier-Bresson can’t be a bad thing either.

Nikon offers two 50mm lenses at f/1.4 and f/1.8. I chose the Sigma 50mm f/1.4 over the Nikon counterparts. For one, the reviews for the Sigma are universally outstanding. Even though bokeh quality is somewhat subjective, the general consensus is that the Sigma is better. For almost the same price as the Nikon 50mm f/1.4, it looks and feels much more solid than the plasticky-looking Nikon equivalent. Furthermore, it has the professional-standard 77mm filter size instead of the 58mm and 52mm filter sizes for the Nikon lenses.

The Sigma is very solid with a nice heft. It’s plastic, but manages to feel upscale and not cheap. It comes with a canvas pouch, a lens hood and a lens cover. It’s made in Japan, which is nice for a lens at this price range. Even my much more expensive Nikon 24-120mm f/4 zoom is made in Thailand. Strangely, there’s no marker on the lens to line up with the camera body, so I had to fiddle around a bit to get it to screw in.

Now onto the test images. All photos are taken with a Nikon D600 in either aperture priority or manual mode with auto ISO sensitivity. The first shoot is a walkaround our neighborhood.

This is a rather cliché shot. The subject is flat so all of it can be in focus. I thought the sharpness is very good.

Exposure 1/1000 @ f/1.8, 100 ISO

Here Kate is inspecting our walkway. In daylight the lens focuses easily. I think focusing works best at this distance. Depth of field is good with the lens wide open and so is bokeh. The 50mm focal length is perfect for portraits that include the upper body or shoulder.

Exposure 1/1250 @ f/1.8, 100 ISO

I love this shot, and not just because of the subject. Because of the closeness, I had to stop down the aperture a bit while focusing on the eyes. Otherwise the other parts of the face would be out of focus.

Exposure 1/50 @ f/5, 1800 ISO

The second shoot was at a ballroom competition at Tufts University where my friends were competing. Here I put the D600 in continuous servo AF mode with 9 focusing points. I shot in manual mode with the shutter speed set at a sufficiently high value to prevent blurring. I also set the AE/AL button to AF-on so that shutter release button just, well, release.

This is a rather flashy couple that clearly dominated the rest of the field. They were quite adept at showmanship. Not surprisingly, they took first place.

Exposure 1/400 @ f/2.2, 720 ISO

Here they are practicing in the corridor above the main floor. The setting is very nice, as is the photogenic couple. This has almost an Instagram feel to it.

Exposure 1/400 @ f/1.8, 3200 ISO

This is at the maximum aperture. Again sharpness is excellent at a range of about 3m. I had several long-distance shots from around 20-40m with continuous servo AF that didn’t turn out very good. The subject was blurry while the background was in sharper focus. Either the autofocus wasn’t working well, or I just didn’t have the right setting. I switched from 9- to 21-point focusing mode and got somewhat better results. In general I think this lens suits close-ups better.

Exposure 1/400 @ f/1.4, 2800 ISO
Exposure 400 @ f/2.2, 3200 ISO

The last shoot is at a friend’s house. I had to use continuous focusing again because the subject was rather, ahem, mobile. Some shots turned out quite blurry even with high shutter speed. I’ll have to look into this more. This shows the nice subject isolation possible with the ridiculously large aperture.

Exposure 1/60 @ f/1.4, 450 ISO
Exposure 1/160 @ f/2.2, 3200 ISO
Exposure 1/160 @ f/2.2, 2800 ISO

In conclusion, I love this lens! I like the ability to just point and shoot without worrying too much about composition. Being so used to carefully composing a shot, I’ve had to resist that impulse a bit and just focus on capturing the moment as it happens. The results look and feel natural and effortless. Needless to say this lens will get a lot more work in the future.