Canon EF 135mm f/2L USM vs Sirui 135mm T2.9 1.8x (Sony E Mount)
Canon EF 135mm f/2L USM vs Sirui 135mm T2.9 1.8x (Sony E Mount)
When comparing Sirui 135mm T2.9 1.8x (Sony E Mount) and Canon EF 135mm f/2L USM, which one is better?
1. Lens Mount Comparison
The lenses each feature different lens mounts — the Canon EF 135mm f/2L USM features a Canon EF while the Sirui 135mm T2.9 1.8x - (Sony E Mount) features a Sony E — and because of this the preference varies. If you have a compatible camera, then of course that lens will be a better choice for you.
Winner: Tied — It depends on your gear
Regarding lens mount: Popular lens mounts are Canon RF and EF, Micro Four Thirds and Nikon Z. Different lens mounts lets you connect different lenses to camera bodies, but some might not be compatible. This can be helped by using an adapter, like a Canon EF to RF adapter.
2. Largest Aperture Comparison
The Canon EF 135mm f/2L USM has the largest aperture of the two lenses at 2 compared to the 2.9 aperture of Sirui 135mm T2.9 1.8x - (Sony E Mount). This means that you get more light to your sensor using Canon EF 135mm f/2L USM wide open, and therefore it might be a better lens in dark situations.
Winner: Canon EF 135mm f/2L USM
Regarding largest aperture: A lower aperture number means that the widest aperture on the lens is larger. This means that more light will hit the sensor and also that the depth of field will be shallower, better separating your subject from the background.
3. Anamorphic Comparison
Winner: Sirui 135mm T2.9 1.8x (Sony E Mount)
Regarding anamorphic: Anamorphic lenses are usually used on cinema cameras and squeezes the image when its recorded, which gives the final, stretched out, image oval bokeh and a different angle of view. The most common lenses, however, are not anamorphic but spherical, which gives a spherical bokeh and is a much cheaper lens design.
Specifications
Full specifications table of Canon EF 135mm f/2L USM and Sirui 135mm T2.9 1.8x (Sony E Mount):
| Canon EF 135mm f/2L USM | Sirui 135mm T2.9 1.8x - (Sony E Mount) | |
 |  | |
| Brand | Canon | Sirui |
| Lens Mount | Canon EF | Sony E |
| Focal Length | 135 mm | 135 mm |
| Largest Aperture | 2 | 2.9 |
| Anamorphic | No | Yes |
| Anamorphic Squeeze Factor | Missing | 1.8 |
| Type | Prime | Missing |
| Image Stabilization | No | Missing |
| Autofocus | Evet | Missing |
| Macro | No | Missing |
| Weather Seal | Yes | Missing |
| Full Frame Coverage | Yes | Missing |
| Lens Hood Included | Yes | Missing |