The difference between a Canon RF 50mm and an EF 50mm lens is mostly about the camera it was made for. RF lenses are made for Canon mirrorless bodies, while EF lenses were made for Canon DSLRs and can be used on mirrorless bodies with Canon’s mount adapter. If you own an RF camera, an RF 50mm is the cleaner fit; if you shoot a DSLR, EF is the natural choice.
Understanding the Two Lines
Canon has made several 50mm lenses in each mount. On the RF side, the lineup includes a fast f/1.2 L model and a compact f/1.8 STM model. On the EF side, the history is longer, with f/1.2 L, f/1.4 and f/1.8 versions over the years. Because there are many models, compare a specific RF lens with a specific EF lens rather than comparing the mounts in general.
A 50mm lens gives a natural field of view and is popular for portraits, street scenes, food and low-light work. Both mounts offer the same basic focal length experience; the difference is in the mount design and what each camera body can do with it.
Mount Differences That Matter
| Trait | RF 50mm lenses | EF 50mm lenses |
|---|---|---|
| Made for | Canon mirrorless (RF) | Canon DSLR (EF) |
| On RF cameras | Direct fit | Needs mount adapter |
| On DSLRs | Does not fit | Direct fit |
| Overall length | Often more compact | Longer with adapter on mirrorless |
| Control ring | On some models | Not on EF lenses |
Adapters work well for most people, but they add length and one more part. Some adapter versions add a control ring or a filter slot, so check Canon’s lineup. The RF mount was designed with a short distance between the lens and sensor, which gives lens designers more freedom, so some RF lenses use newer optical layouts.
How to Choose
- Check your camera mount. A DSLR cannot use an RF lens, so that decides things at once.
- If you have an RF camera and an old EF 50mm, try it with the adapter before replacing it. Many EF lenses work very well that way.
- Consider the aperture you want. f/1.8 suits everyday use and light carry. f/1.4 and f/1.2 offer stronger blur and more light for dim venues.
- Check the focus motor and the maker’s notes if you shoot video, since newer designs tend to focus more quietly.
- Confirm size and weight on Canon’s page for the specific model.
Baseline Settings for a 50mm
These are general guidelines, not fixed rules. For portraits, try roughly f/1.8 to f/2.8. For street scenes in daylight, f/5.6 to f/8 with a shutter speed of roughly 1/250 and faster works for many people. For still subjects indoors, a shutter speed around 1/60 or faster is a sensible floor if you hold the camera steadily.
FAQ
Does an EF 50mm lose features on an RF camera?
Most core functions carry over through the adapter, but exact behavior depends on the lens and body. Check Canon’s compatibility notes.
Is the RF 50mm worth upgrading to?
If your current EF lens works well and you like the results, there may be no need. Upgrade when size, features or the aperture you want justify it.
The Short Version
RF and EF 50mm lenses give the same field of view, and the mount decides what fits your camera. Choose RF for a native mirrorless setup, and choose EF if you shoot a DSLR or already own a lens you like.
