Sigma is known for making high-quality affordable lenses. Here’s why the new Sigma 50mm f/1.4 DG DN lens is a lens you should consider.
As a portrait shooter, a 50mm lens is one of my most used focal lengths. I've owned several Sigma lenses in the past and have always been impressed, especially for the price. I like the matte black look and the silver "A" in the body of the lens for the Art line. The Art lenses are the higher-end lenses, with the other lines being the Sports line and Contemporary line, which are generally not as sharp as the Art lenses. This lens has 14 glass elements in 11 groups and 11 rounded diaphragm aperture blades for smooth bokeh rendering. The minimum aperture is f/16.
I recently had the opportunity to use it on two separate portrait shoots to test its capabilities. Overall, I found this to be a great lens. Here are the tests I did and what I concluded.
Sigma's New HLA Auto Focus Mechanism
This is now Sigma's second lens to have the HLA (High-response Linear Actuator) autofocus mechanism. It eliminates noise from focusing and lets you quickly grab focus. To test the difference, I used my 50mm f/1.2 G Master lens. I focused on something close and then I focused on something far. When I was holding it in my hand, I could hear the motor and I could feel the vibration of the moving parts in my hand. When I switched lenses and put on the Sigma and did the same test, there was no noise and no vibration.
The lens focusing system is important not just to get focus correct, but to get it correct fast enough so you don't miss shots. The worst lens I ever bought was the Sony 85 f/1.4 G Master. Not only did it have noisy focusing problems, it missed focus a lot. It was constantly hunting back and forth, trying to lock onto something. By the time it locked on, the moment was gone. I had so many missed shots with that lens. The Sigma does not suffer from that problem. I had no problem getting focus quickly in low-light situations or when subjects were moving when I was shooting video.
Lens focusing noise is only really an issue if you are shooting video in a library. The real question is how this HLA system stacks up as far as grabbing focus quickly and giving you sharp images. I tested this lens both wide open and at tighter apertures with strobes, LED, and in an ultra-low light situation lit with just candles. It was able to handle every scenario. Below are some unedited images that were shot full body, but cropped in on just the face so you can see the focus on the eyes and on the face.
Here are images shot with strobe and apertures f/5.6 to f/11:
Here are images shot wide open at f/1.4:
Here are images shot wide open using just candlelight:
Another test I decided to perform was with objects moving fast in front of the subject's eyes. When I shoot in my rain room in my studio, when raindrops fall in front of a subject's eyes, it can affect the autofocus. So, I wanted to test the focusing system with someone throwing confetti in front of their face. The eyes stayed in focus the entire time, and the lens did not have to hunt for focus.
The Sigma 50 f/1.4 has a solid build quality. It is weather-sealed to protect from splashes and the rain. The body features an aperture ring, a switch to toggle from manual focus to autofocus, and an AFL button. There is also a slide that locks the aperture ring so you don't accidentally change the aperture while shooting.
It is 3.1 x 4.3 in. and weighs 23.6 oz. Since I usually shoot with a Sony 50mm f/1.2, I immediately noticed that it was much lighter and slightly narrower, which made it easier to balance when shooting video handheld.
What I Liked and What Could Be Improved With This Lens
My shooting style is to shoot fast and capture a lot of movement. I often shoot on burst and capture movements like running a hand through the hair or walking in order to get more natural-looking shots. That also makes it harder to catch focus every time. Compared to my Sony 50mm f/1.2 lens, this had a slightly higher number of shots with missed focus, but it hit focus every time when I was doing more static poses on the seamless paper. Out of about 1,200 shots, about 15 of them were not in focus, whereas, with my Sony lens, it's about 10 on average when I'm shooting fast movement. Overall, it's not a huge concern, especially given that the Sony lens costs almost twice as much,
In general, I loved how it was able to grab focus so quickly, especially in low-light conditions. I shoot mostly full-body portraits and I use a Sony a7R IV, which is a 61-megapixel camera and gives me the ability to crop in on faces when I shoot full body and still have enough resolution to have a usable photo. For these tests, I shot tighter portraits focusing on just the face as well as full body shots. In both instances, the focus on the eye was superb and I could not tell the difference between my more expensive Sony lens.
This is a really nice lens, especially for the price. It has an overall excellent autofocus capability, especially when tested in movement and low-light scenarios where it performed almost as well as a lens that costs over twice as much. It is aesthetically pleasing and has a solid build quality and weather-sealing. The pictures came out incredibly sharp with no distortion or chromatic aberration.
For more details and some behind the scenes, check out the video above. You can purchase yours here: Sigma 50mm f/1.4 DG DN lens.