EF Canon USM 50mm f/1.4 vs. Canon EF STM 50mm F/1.8- Which Canon Standard Prime Lens is better?


Given all the brands and lens series available out here, selecting one can get quite difficult. For example, Canon alone makes a vast collection of different lens types, among other items. Here, yup will find a comparison review of 2 popular Canon lenses, both of which are equipped to perform as best as they can. Here is EF Canon USM 50mm f/1.4 vs. EF Canon F/1.8 50mm STM.

Hi, I am N AME and I have been a professional photographer for a little bit over 5 years now. Given my profession and the time I spend at my studio, many people often seek camera and camera accessory advice from me, regularly. One of the more popular concerns many people have is with choosing the right lens. As a pro, the best or right lens will always depend on the task at hand. Here, I am going to go into an in-depth review and comparison of two popular lenses for the EF Canon USM 50mm f/1.4 and the Canon EF STM 50mm F/1.8. Both these lenses are popular lenses from Canon, and with good reason.

If you are interested in EF Canon USM 50mm f/1.4 vs. Canon EF STM 50mm F/1.8, read on for further insight.

What are the differences between EF Canon USM 50mm f/1.4 and Canon EF STM 50mm F/1.8?

EF Canon USM 50mm f/1.4
Canon EF STM 50mm F/1.8
Optics design
Gaussian Optics, 7 elements in 6 groups of which 2 are made using high refraction glass
6 elements in 5 groups
Lens type
Maximum Aperture
Motor type
Ultra Sonic Motor
Stepping Motor

EF Canon USM 50mm f/1.4 vs. Canon EF STM 50mm F/1.8- How these two compare

Both the Cannon EF 50mm USM and 50mm STM are both Prime lenses from the same maker. While there are many optical and physical similarities between both instruments, there are even more differences to the design etc that makes either lens not only functional but different. Here is a quick comparison between both lenses.


Optics are an essential specification for lenses. This is among those attributes that will make or break a lens. There are several attributes that both instruments share especially with respect to optics For instance, both lenses. Neither of these devices is equipped with an aperture ring nor do they have any zoom capabilities: no power zoom, no zoom method and no zoom ratio.

Lens configuration which is basically the layout or design effected on an instrument is similarly different on either lens. For instance, the F/1.4 USM comes with 7 optical elements arranged in 6 groups. Alternatively, the F/1.8 has a 6 element configuration arranged in 5 groups.

A notable optical difference between the EF Canon USM 50mm f/1.4 and the Canon EF STM 50mm F/1.8 is their aperture at maximum. As you can tell from the model names, the former has a maximum F/1.4 aperture, making it a faster lens at wide.

Additionally, the Canon F/1.4 USM produces images with better Bokeh compared to the F/1.8 STM. This is due to the difference in the number of aperture blades on either lens. While the F/1.4 USM has an 8 blade design, the F/1.8 has only 7 diaphragm blades. Since Bokeh can be directly influenced by the number of blades, the F/1.4 USM takes the win in this area.

Size and build quality

The size of a lens is influenced by a number of factors. Similarly, said size influences other factors including the price. This is of course in combination with other factors. Size for instance in terms of weight will influence portability and convenience. Alternatively, size in terms of dimensions will influence storage, and in other instances, portability.

The reason the Canon F/1.8 STM is much lighter than the F/1.4 is because the later is made almost exclusively with a plastic material.

Autofocus motor

An autofocus motor is a common component for lens parts. It is part of a system that relies on the autofocus system to deliver information or instructions required for proper focusing. Once various focusing components play their respective roles in this process, the Autofocus motor then receives a signal to focus the lens to the correct settings. The Canon F/1.4 USM utilizes an Ultra Sonic Motor type while the Canon F/1.8 STM relies on the Stepper motor type for focusing purposes. While we are still on the topic of focusing, both these instruments feature full time manual focusing override.

We must mention however, the former, USM model uses the unit focus method while its counterpart relies on internal style of focusing.


The amount of money you intend to spend on a lens holds a significant influence in the choice of lens to go with. In this instance, the Canon EF 50mm f1.8 STM is well over 200 dollars cheaper than the Canon EF 50mm f1.4 USM. This might not seem like a big deal since lenses can get quite expensive. However consider this: you will not spend as much as this difference purchasing the Canon EF 50mm f1.8 STM.

EF Canon USM 50mm f/1.4 vs. Canon EF STM 50mm F/1.8- A comparison review

Canon EF 50mm F/1.4 USM- Overview and key features

The EF 50mm F/1.4 USM as it is commonly known is marketed as a high performance standard lens with a fast max aperture in addition to its rapid focusing system. This lens is not only compact, but also well equipped to deliver superb performance in all fields of photography. Take a look at some of the features that make this lens so capable.

This lens is designed as a standard lens for a full frame format and an angle view. Overall, the build is okay with quality material and a decent focus ring function. This lens is great for low light indoor action where flashing is not ideal. Specifically, this lens has the optics for full body optics in addition to wide field shots including geographic and tourism landscapes. The compact nature of this lens coupled with its light weight nature makes it quite portable.

The optical system utilizes 7 elements in 6 groups of which 2 are made using high refraction glass. It combines Gaussian optics with two refraction lenses elements that allow the user to capture very clean and crisp images. These ensure astigmatism is eliminated in addition to suppressing the astigmatic difference. With its wide aperture and optic features, this lens is ideal for landscape images, travel shots or even portrait types. At its price, the EF Canon USM 50mm f/1.4 offers great value for your money.

An ultra sonic motor USM on this system drives the autofocus quite quickly and with very little noise. Unlike most similar Canon lenses, this model uses the micro type USM with a manual full time override that ensures high degree subject isolation. To this accord, the Cannon EF 50mm F/1.4 USM a natural blur in the background that elevates photograph aesthetics.

The optics on the EF 50mm F/1.4 USM have the super multilayer coating to help reduce flare and ghosting greatly. The super spectra coating as it is known helps ensure there is a balance with the color in addition to enhancing the contrast. Notably, both flare and hosting are common problems with many digital camera, both of which are caused by light bouncing off this camera’s sensors. The coating helps improve and in many instances, optimize performance on the EF 50mm F/1.4 USM.

Technical specifications

Some of the important technical specifications on the EF 50mm F/1.4 USM include a fast F/1.4 aperture with a standard 46 degree angle of view. Additionally, this lens has an aspherical lens element with a 58mm filter size and 45cm focusing distance. A minimum aperture of F/22 with a magnification of 0.15X and 50mm focal length are several other optic specifications on this lens. In total, this instrument weighs 290grams, or 10.2oz. For a standard traditional 50mm lens, the EF 50mm F/1.4 USM is on the larger side. However, it is still quite manageable and is similar in size with several other bulky 50mm lenses.

On a full frame sensor, the diagonal angle of view is at 47o. Alternatively, the diagonal with and APS-C 80mm equivalent is 31o.

What we like

  • The maximum aperture provides crisp clear imaging
  • Comes with USM for smooth, quiet and quick focusing
  • Superior peripheral brightness thanks to the large aperture
  • Inexpensive
  • Micro type autofocus with a full time manual override
  • Great optics for great image quality

Issues with the EF 50mm F/1.4 USM

One of the biggest issue with the EF 50mm F/1.4 USM has to be the focus operation malfunction which simply means the EF 50mm F/1.4 USM has difficulty focusing. During AF or MF mode when you move the focus position all the way to the end from the . Fortunately, affected models have since been recalled for inspection.

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Canon EF STM 50mm F/1.8– Overview and key features

The Canon EF STM 50mm F/1.8 is popular for the sharpness of its images and the value of money the instrument delivers in general. However, don’t let the light to the touch exterior fool you. This lens is capable of quite adequate performance. Here are some of the features that makes this possible.

If you are familiar with Canon lenses then you know that like with many lines of a certain products, there are top tier products, mid tier and so forth. The Canon EF STM 50mm F/1.8, although seemingly built with lower tier quality, combines various features with it optics among other things to deliver the quality sharpness performance it is so popular for. It is priced as a low tier lens but functions at new mid-top tier level.

This feather weight lens utilizes a plastic like material as the exterior. Additionally, the lens mount is made of a plastic material: which is adequate for this instrument. The result is a compact and lightweight lens that is great for moving around without becoming too bulky, while still delivering clear sharp images. Additionally, the EF Canon F/1.8 50mm incorporates improved focus ring placement to its design that is mean to make manual focusing even easier.

Because sharpness is one of the Canon EF STM 50mm F/1.8 best feature, it is well equipped optically to deliver sharp images. In fact the lens can achieve sharpness of decent proportions at F/1.8 however, at F/2,8, the instrument reaches sharpness even lenses on top tier levels cannot achieve.

Focusing using this lens is operated using a micro motor i.e. the Stepping gear motor that delivers quiet, almost silent adjustments quite quickly. With this STM motor technology, the EF Canon F/1.8 50mm can focus fast and . Additionally, the circular seven blade mechanism design on this lens helps to confer that beautiful blur on images that makes them so appealing. You may utilize the Movie Servo Autofocus for videos or still photographs, either way, the result is the same.

Because of its design, the Canon EF STM 50mm F/1.8 is a good option for photography in low light or indoor environments where a flash is undesirable. It is especially great fort taking portraits: Full body or even head/shoulder portraits. It is easy to hurl around tanks to the lightweight material used to manufacture the lens.

Issues with the Canon EF STM 50mm F/1.8 Lens

While it might not particularly been an issue, you might find it difficult at first to comb through the existent Canon EF F/1.8 lens models available. The process is somewhat difficult for anyone not conversant with the history of the Canon EF STM 50mm F/1.8 Lens.

What we like

  • Lightweight and easy to use
  • Quality optics

What we don’t like

  • Nothing extraordinary about build quality


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Verdict: So which one is better? The EF Canon USM 50mm f/1.4 or the Canon EF STM 50mm F/1.8?

After looking at how each of these lenses is built and what either option has to offer, the better standard prime lens has to be the Canon EF STM 50mm F/1.8. While is it the cheaper lens with comparably poorer build quality, the F/1.8 STM has better close ups, is smaller, lighter and generally more convenient.


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