In this photo shoot, I used three great fixes:
The differences in perspective at these focal lengths, the nature of the background blur and the overall feel of the photographs will be visible below.
As you can see, all lenses give good blur in half-length portraits. A fifty dollar will give a boring and overloaded background in a full-height portrait, but in this test I did not take such photos.
Personally, I like the first series of pictures better. photo at 135mm with maximum space compression and a very blurry photo. On the second series of shots I am more impressed by first frame, made at 50mm. It conveys more volume and play of light and shade.
When photographing a girl with columns, I had to move a little. Because of this, on third frame at 135mm, the girl's face is mostly in shadow. Although in the first photo there is clearly more light on the face. 135mm limits the photographer's location more than 50mm, which is always easy and convenient to shoot with. But if you're shooting outdoors, the 135mm focal length won't be a problem.
Here is a frame at 85mm:
Here, this focal turned out to be the most appropriate. There was about a meter away from the wall, a window to the right. If I had shot at 135mm, the background would have been washed out and lost texture. 50mm would capture a lot of unnecessary things in the frame (window frame, pipes on the wall, etc.).
Here are two very similar shots at 85mm and 135mm. In this case, 85mm looks better because allows you to more competently compose the frame. Stronger blurring of the bokeh doesn't matter here.
Here is a frame at 135mm:
Here I just want to demonstrate the ability Canon 135mm f2L blur background into trash. The background was very complex and ugly. The stairs, people, columns, window frames - all these unnecessary details were washed away, while maintaining the emphasis on the protagonist.
This test presents very similarly cropped photos to emphasize perspective at focal lengths. 50mm, 85mm, 135mm... As you can see, in such portraits you can successfully use any of the lenses listed. The difference in shooting conditions and the photographer's vision.
85mm remains the most functional portrait lens... 135 helps when you want to put a strong emphasis on a person by compressing perspective and noticeably blurring the background.
50mm can be interesting under certain conditions when you want to play with the background. In most cases, this focal length can be suitable for half-length portraits, but absolutely not suitable for full-height photographs. Tests 50mm versus 135mm in full-length photo you can see here.
Video review Canon 85mm f1.8:
Video review-comparison Canon 135mm f2L VS Canon 70-200 f4L: