Sony vs. Sigma - Rendering ComparisonMarc Heijligers, 06-02-2016
On this page you’ll find some crops of the out-of-focus scene for detailed comparison between the OoF rendering of both lenses.
Summarized ResultsOverall, the Sigma has a better bokeh rendering. The bokeh balls are more solid, with less disturbances due to aspherical elements (e.g. onion rings), and it renders OoF objects smoother.
For comparison reasons, also some crops showing the bokeh of the Sony FE 55mm 1.8mm have been added. The bokeh of the 55mm is of the same quality of the Sigma at open apeture, and a bit better when closed down. If bokeh is the prime reason for buying a lens, the question whether a 55mm lens doesn’t make more sense than a 35mm.
Test ConditionsThe camera is put at the minimum focus distance plus a few centimeters (reference is the Sony FE 35mm F1.4), to obtain the most smooth bokeh. The Sony FE 35mm F1.4 is tested mounted on an A7RII, and the Sigma ART 35mm F1.4 mounted on a NIkon D800. The A7RII pictures have been scaled to the D800 resolution (from 42Mpix to 36MPix) to make them easily comparable.
The A7RII photos have been made with Steadyshot turned OFF, Silent Shooting turned ON, and a timer (but the differences are hardly visible with complementary settings in this specific setup). Pictures are taken in RAW, and processed in Lightroom with the Camera Neutral setting, and with Lens corrections enabled.
The scene is shown below. The focus point is on the orange lens box. The scene contains some out-of-focus elements, the main ones are:
- Lampshades with small holes, creating small light sources.
- Test image on the computer
- Painting with colors on the back
Besides the full picture showing the overall rendering, a crop is taken at the lights sources in the lampshades, to study the shape and content of the bokeh balls.
Detailed ComparisonUse the filter button below to select which cases you want to see and compare in detail (the buttons will limit the selection), and use the slider to compare the Sony (on the left) and the Sigma (on the right).
Bokeh f1.4 - The Sony shows onion rings, the Sigma renders smoother.
Bokeh f2.8 - The bokeh of the Sony is busy compared to the Sigma, and shows onion rings due to its aspherical lens elements. The Sigma renders clearly nicer.
Bokeh f5.6 - Also at f5.6, the rendering of the Sigma is softer, and the form of the bokeh balls is more even.
Bokeh - If bokeh is of main concern, the question is why to stick to expensive 35mm lenses like the Sony (€1699!!!). If you compare it to the bokeh of the less expensive Sony 55mm FE 1.8 (on the right side - also not cheap at €999), the 55mm shows a much more smooth focus than the Sony (or Sigma).
Bokeh - Comparison between the Sigma 35mm (left) at f1.4 and the Sony 55mm FE 55mm at f1.8 (at the right). The Sigma is a tad softer (but realize that for 1-1 comparison I had to scale the 55mm picture by 65%!)!
Bokeh - Comparison between the Sigma 35mm (left) at f2.8 and the Sony 55mm FE 55mm at f2.8 (at the right). I would judge the bokeh at the same quality level.
Full Scene f1.4 - Not realizing that the Nikon D800 is a bit higher than the A7RII on the same tripod, the composition shift a bit. Furthermore, the iPad started to show a menu after a while, so showing white stripes at both ends. Last but not least, there are als differences in the color rendering of both cameras. But all ’n’ all, not too much differences in practice, I would say the Sigma is a tad softer.
Full Scene f2.8 - The Sigma has a smoother rendering, with bigger bokeh balls.
Full Scene f5.6 - The Sigma has a smoother rendering, with bigger bokeh balls.
Full Scene- The Sony 35mm at f1.4 versus the Sony 55mm at f1.8. The scene is not 100% the same (as the camera is positioned at the minimum focus distance plus a few centimers to obtain most smooth bokeh). Therefore, I’ve cropped the 35mm image to get some simular scene. It is obvious that the bokeh of the 55mm is smoother than the 35mm.
Full Scene- The Sigma 35mm at f1.4 versus the Sony 55mm at f1.8. The scene is not 100% the same (as the camera is positioned at the minimum focus distance plus a few centimers to obtain most smooth bokeh). Therefore, I’ve cropped the 35mm image to get some simular scene. The quality of the bokeh is equal to my eyes.