Canon RF50mm F1.8 STM Lens, Fixed Focal Length Prime Lens vs SIRUI
Updated July 2026 — Canon RF50mm F1.8 STM Lens, Fixed Focal Length Prime Lens wins on price and size, SIRUI wins on weight and build.
The Canon RF50mm F1.8 STM lens is a more affordable and versatile option for photographers, while the SIRUI 20mm T1.8 Anamorphic lens excels in cinematic features for filmmakers.
Why Canon RF50mm F1.8 STM Lens, Fixed Focal Length Prime Lens is better
Price
Canon lens is significantly cheaper at $219.
Weight
Canon lens is lighter, making it easier to carry.
Versatility
Canon lens is suitable for various photography styles.
Why SIRUI is better
Cinematic Quality
SIRUI lens offers a unique 2.35:1 aspect ratio.
Autofocus Features
SIRUI lens has advanced eye-tracking autofocus.
Low-Light Performance
SIRUI lens provides superior low-light capabilities.
Overall score
Specifications
| Spec | Canon RF50mm F1.8 STM Lens, Fixed Focal Length Prime Lens | SIRUI |
|---|---|---|
| Aperture | f/1.8 | T1.8 |
| Focal Length | 50mm | 20mm |
| Compatibility | EOS R | E Mount |
| Lens Type | Prime | Anamorphic |
| Focus Type | Autofocus | Manual/Auto |
Dimension comparison
Overview of the Canon RF50mm F1.8 STM Lens
The Canon RF50mm F1.8 STM lens is a compact and lightweight option designed for EOS R series mirrorless cameras. Priced at $219.00, this lens is not only affordable but also delivers impressive optical performance with a large f/1.8 aperture, making it ideal for low-light photography. This fixed focal length lens offers versatility for various shooting scenarios, from portraits to landscapes.
The lens’s design optimizes color balance and minimizes ghosting and flare, making it a reliable choice for photographers seeking quality without breaking the bank. Its stepping motor technology ensures smooth and quiet autofocus, which is particularly beneficial for video recording. Overall, the Canon RF50mm F1.8 STM lens stands out as a great entry point for photographers looking to enhance their EOS R camera experience.
Overview of the SIRUI 20mm T1.8 Anamorphic Lens
The SIRUI 20mm T1.8 Anamorphic lens is a premium option priced at $599.00, targeting cinematographers and video creators. With a 1.33x squeeze factor, this lens provides an immersive cinematic view with a 2.35:1 widescreen ratio, making it a unique offering for filmmakers. Its ultra-fast T1.8 aperture enhances low-light performance, allowing for clearer night scenes and soft bokeh, which are essential for capturing cinematic visuals.
This lens supports both manual and autofocus modes, powered by a precision stepping motor. Its compatibility with APS-C and Super 35 sensors makes it a versatile choice for various filming situations. The SIRUI 20mm T1.8 lens is compact and lightweight, making it suitable for handheld shooting and gimbal use, ensuring creators can achieve high-quality visuals on the go.
Price Comparison
When it comes to price, the Canon RF50mm F1.8 STM lens is significantly more affordable at $219.00 compared to the SIRUI 20mm T1.8 Anamorphic lens, which costs $599.00. This represents a price difference of $380, making the Canon lens about 63% cheaper than the SIRUI option. For those on a budget or new to photography, the lower price point of the Canon lens makes it an attractive option without compromising on quality.
In contrast, the SIRUI lens, while more expensive, offers unique features designed for filmmakers, justifying its higher price tag. Buyers must consider their specific needs—whether they are seeking a versatile photography lens or a specialized tool for cinematic projects—when evaluating these price points.
Build Quality and Design
The Canon RF50mm F1.8 STM lens is designed to be compact and lightweight, making it easy to carry and handle. Its sleek design is optimized for compatibility with the EOS R camera body, ensuring that it feels balanced when mounted. The lens also features a control ring for direct setting changes, enhancing user experience and efficiency.
On the other hand, the SIRUI 20mm T1.8 Anamorphic lens, while also lightweight at 480 grams, is built specifically for demanding shooting conditions. Its design incorporates a robust construction suitable for professional use, and the lens is optimized for APS-C and Super 35 sensors, providing excellent image clarity. The thoughtful engineering behind both lenses reflects their intended use, with the Canon lens focusing on ease of use for photographers and the SIRUI lens catering to the needs of filmmakers.
Optical Performance
The Canon RF50mm F1.8 STM lens excels in optical performance thanks to its large f/1.8 aperture, which allows for excellent low-light capabilities and beautiful background blur. Its PMo aspherical lens helps suppress aberrations, while specialized coatings reduce flaring and ghosting. This combination of features ensures that images are vibrant and true to life, appealing to photographers who prioritize image quality.
Conversely, the SIRUI 20mm T1.8 Anamorphic lens is designed specifically for cinematic applications, providing a unique 2.35:1 widescreen aspect ratio that enhances storytelling through visuals. The T1.8 aperture also aids in low-light performance, but its primary focus is on delivering cinematic depth of field and perspective that is ideal for video. This lens provides filmmakers with the tools needed to create striking visuals, making it a strong contender for projects requiring a distinctive look.
Autofocus and Usability
The Canon RF50mm F1.8 STM lens features a stepping motor that offers smooth and quiet autofocus, making it suitable for both still images and videos. This technology enhances usability, especially for those shooting in various environments where noise might be a concern. The lens also includes a control ring for easy adjustments, adding to its user-friendly design.
In contrast, the SIRUI 20mm T1.8 Anamorphic lens provides both manual and autofocus options, with advanced eye-tracking capabilities. This flexibility allows cinematographers to switch between modes based on their shooting style and needs. The lens’s autofocus lock feature adds to its usability in dynamic shooting situations, giving creators control over their focus points. Both lenses cater to different user preferences, with Canon focusing on straightforward photography and SIRUI providing advanced features for filmmakers.
Intended Audience
The Canon RF50mm F1.8 STM lens is primarily aimed at photographers who are looking for an affordable yet high-quality lens to complement their EOS R series cameras. Its versatility makes it suitable for a wide range of photography styles, including portraits, landscapes, and everyday snapshots. This lens appeals to both beginners and experienced photographers seeking a reliable, compact option.
In contrast, the SIRUI 20mm T1.8 Anamorphic lens targets professional video creators and filmmakers who require specific features for cinematic storytelling. Its unique design and optical capabilities make it well-suited for projects that demand high-quality visuals and creative control. This lens is ideal for those in the film industry or independent creators looking to elevate their video production with a cinematic flair.
Which should you buy?
Choosing between the Canon RF50mm F1.8 STM lens and the SIRUI 20mm T1.8 Anamorphic lens ultimately depends on your specific needs and budget. If you are a photographer looking for a versatile, compact, and affordable lens, the Canon RF50mm F1.8 STM lens at $219.00 is an excellent choice. It provides outstanding optical performance and user-friendly features that cater to a range of photography styles.
However, if you are a filmmaker seeking to create cinematic visuals with a unique 2.35:1 aspect ratio, the SIRUI 20mm T1.8 Anamorphic lens offers advanced features and superior image quality, albeit at a higher price of $599.00. Your decision should align with your creative goals, whether in photography or filmmaking, to ensure you invest in the lens that best suits your artistic vision.

