The Canon RF 28-70mm f/2L USM (Amazon, B&H) is supposed to be a photography lens, though it’s a video lens in disguise.
And a drool-worthy one at that!
In this article let’s take a comprehensive look at the important features and specifications of the Canon RF 28-70mm f/2L USM lens and see how good it will perform specifically for video, cinematography and filmmaking.
The aim of this article is to provide you with enough information and perspective so you can decide for yourself whether this lens is right for your film or video.
Important: This article is a comprehensive overview of the lens with available information; and an analysis based on our experience shooting for almost two decades. It is not a hands-on review. If and when we get hold of the lens we’ll be sure to publish a detailed review. If this is not your cup of tea you can stop reading.
Click to what you want quickly:
- TLDR;
- EF vs RF:
- Features:
- Control:
- Basics:
- Alternatives to the RF 28-70mm f/2L USM.
TLDR;
What you need to know for video work about the Canon RF 28-70mm f/2L USM (Amazon, B&H):
- The Canon RF 28-70mm f/2L USM is an amazing and groundbreaking lens. It promises world-class optical quality in a large aperture (f/2) in a very useful zoom range. What’s not to like?
- The constant f/2 aperture is legendary for video work. Try finding another one for full frame sensors.
- Focus ring can be changed to fly-by-wire for follow focus work.
- Control ring can be de-clicked for a small fee at a Canon service center for aperture transitions.
- The lens does not have Image Stabilization.
- Great for dual pixel autofocus for video.
- The lens doesn’t extend while zooming, and it is inner focus.
- It is not a parfocal lens.
- It exhibits breathing.
Can be great for the following types of filmmaking:
- Wedding filmmaking
- Documentary filmmaking
- Shorts and feature films
EF vs RF: What’s the difference?
Difference between the RF and EF mount
Both are lens mounts specific to Canon. Let’s take a look at some important distinctions.
Flange focal distance
The RF is a new lens mount, with a smaller flange focal distance.
Here’s how the flange focal distance compares:
| Mount | Flange Focal Distance |
|---|---|
| RF | 20mm |
| EF | 44mm |
EF lenses were designed for DSLRs. Now with the mirror gone, that’s space and weight savings. However, that’s not the only advantage.
Canon (and every one else) maintains the smaller flange focal distance allows for larger apertures (for some focal lengths), better corner to corner sharpness and reduced light fall off.
Ergonomics
RF lenses are supposed to be lighter, making them easier to handle for photography, but slightly problematic for video. Weight gives better stability and smoother movement for most use cases. For gimbal, drone and steadicam use, the lower weight is an advantage because a lighter lens puts less strain on motors, and the human arms that have to hold it up.
The RF mount is equipped with 12 communicator pins compared to 8 pin connection of the EF mount. Canon claims this contributes towards quicker autofocus, better AF tracking and improved image stabilization.
Canon has redesigned the focus actuators for a hassle-free filming. They claim the new Nano USM and Dual Nano USM have been designed for video. Canon claims that the introduction of these actuators in RF lenses will result in a quieter and quicker autofocus.
The last major change is in the optics. Canon have redesigned the optics from the ground up to account for the smaller flange focal distance. This one simple change considerably changes the optical characteristics and challenges.
Naturally the prices of RF lenses match the high quality Canon have put into these series! The assurance is, the quality isn’t compromised, and with proper care Canon RF lenses should last for years. Let’s compare the EF version of the 24-105mm with its newer RF counterpart.
Canon EF 24-70mm f/2.8L II USM vs RF 28-70mm f/2 L USM
Most people won’t think of upgrading from the EF 24-70mm f/2.8 to this lens, though here’s a comparison so you understand the major differences.
| Lens | RF 28-70mm f/2 | EF 24-70mm f/2.8L II |
| Lens Construction | 13 groups, 19 elements | 13 groups, 18 elements |
| Filter thread | 95mm | 82mm |
| Closest Focusing Distance | 0.39m / 1.28 ft | 0.38m / 1.25 ft |
| Size | 103.8 x 139.8mm | 88.5 x 113mm |
| Weight | 1430g | 805g |
| Lens Control | Ring control | none |
| Image stabilization | none | none |
| Aperture Blades | 9 blades | 9 blades |
| Maximum Aperture | f/2 | f/2.8 |
| Minimum Aperture | f/22 | f/22 |
| Diagonal Angle of View | 75° – 34° | 84° – 34° |
There are major differences, of course. It’s not a fair comparison.
The Canon EF 24-70mm f/2.8L II USM (Amazon, B&H) is way. lighter and smaller than the RF 28-70mm f/2L USM (Amazon, B&H).
However, you have to consider the weight and the size of the lens adapter to adapt the EF lens to your RF camera. The 24-70mm has a wider zoom range, and is more useful in that regard. The 28-70mm compromises a bit of wide angle focal length to hit that f/2 aperture and still stay within an acceptable size.
RF lenses come with a special customizable control ring this can be customized to change exposure on the go. This is only available on cameras that natively have an RF mount.
Now let’s see how the RF 28-70mm f/2 compares to an RF 24-70mm f/2.8, because that might be a more practical conundrum.
Canon RF 24-70mm f/2.8 L IS USM vs RF 28-70mm f/2 L USM
Here are the differences:
| Lens | RF 28-70mm f/2 | RF 24-70mm f/2.8 |
| Lens Construction | 13 groups, 19 elements | 21 groups, 15 elements |
| Filter thread | 95mm | 82mm |
| Closest Focusing Distance | 1.28 ft / 0.39m | 0.69 ft./0.21m (wide) 1.25 ft./0.38m (telephoto) |
| Size | 103.8 x 139.8mm | 88.5 x 125.7 mm |
| Weight | 1430g | 900g |
| Lens Control | Ring control | Ring control |
| Image stabilization | none | 5 Stops |
| Aperture Blades | 9 blades | 9 blades |
| Maximum Aperture | f/2 | f/2.8 |
| Minimum Aperture | f/22 | f/22 |
| Diagonal Angle of View | 75° – 34° | 84° – 34° |
The Canon RF 24-70mm f/2.8L IS USM (Amazon, B&H) is lighter and smaller than the RF 28-70mm f/2L USM (Amazon, B&H).
It has image stabilization, and is the better option for gimbal work. It also focuses closer at the wide end. If you need a working-person’s all-round professional lens that will get a lot of jobs done, the RF 24-70mm f/2.8L IS USM is your lens.
The Canon RF 28-70mm f/2L USM is in a different class. It will appeal to those who might use it on a tripod or dolly, and with an f/2 aperture it will be tremendous on any film set. And, it doesn’t extend like the 24-70mm, so it will fit right in on a camera rig. It also has what they call Air Sphere Coating, to reduce flares.
They just never made them like this till 2020. You’d pick the Canon RF 28-70mm f/2L USM (Amazon, B&H) for pure image quality and cinematography.
Features
Coverage
The Canon RF 28-70mm f/2L USM (Amazon, B&H) is a full frame lens. It is designed to completely cover a sensor the size of 36mm x 24mm.
If you are considering this lens for an APS-C sensor or other cinema camera, check out this article:
Focal Range
The minimum focal length is 28mm. This is considered wide on a full frame 35mm sensor. However, it’s not that wide.
The maximum focal length is 70mm. This is considered mid telephoto on a full frame 35mm sensor. 70mm f/2 is great for portraiture and closeups, and can replace a lot of primes.
This focal range is very useful. It means you can cover an event or film scene in a room with the wide end. If you’re standing in a large hall at the other end, the 70mm end can be very useful. This is why this focal range is popular, and Canon has given it the “L” moniker.
It does come with its set of compromises. When you try to get that wide of an aperture at f/2 you can only get so much zoom.
Aperture
The maximum aperture is f/2 and the minimum aperture is f/22. This is absolutely remarkable for this focal range.
Having a constant aperture is a great option for video and cinematography. Imagine you’re covering a scene or event where the light doesn’t change. You can move quickly from wide to telephoto at a fixed aperture and not have to worry about compensating for exposure.
The Canon RF 28-70mm f/2L USM (Amazon, B&H) has 9 rounded diaphragm blades. This ensures a smooth bokeh (Canon knows what they are doing!). However, if you want more blades, you might want to take a look at the Canon Sumire primes. Be warned, even after that you’ll return to this baby!
Resolution
From Canon’s official MTF chart:
The Canon RF 28-70mm f/2L USM (Amazon, B&H) manages to stay amazingly consistent throughout the zoom range. The sharpness is equally outstanding at both ends.
With the variance in the Sagittal and Tangential lines, you can infer (somewhat) that the bokeh won’t be as smooth as the best prime lenses on the planet. But why should it?
I think most people looking for a versatile lens in this price range will not be disappointed by the optical quality.
If you are curious and want to read the MTF chart for yourself. Here’s a guide on how to read them easily.
Close Focus
The closest focusing distance is 0.39 meters or 1.28 feet. I believe it stays consistent throughout the focal range.
No complaints.
Image Stabilization
The RF 28-70mm f/2L USM (Amazon, B&H) has no Image Stabilization (IS). It would have probably made the lens a lot heavier.
This omission makes the decision difficult for a filmmaker or a cinematographer for gimbal or handheld use. You can always get a gimbal or a rig for handheld work, but it does add to the expense (and weight) of shooting with this lens.
Pairing this lens with a Canon EOS R5 or Canon EOS R6 can give you some stabilization, so all is not lost.
Is it Parfocal?
The Canon RF 28-70mm f/2L USM (Amazon, B&H) is not a parfocal lens. To know what a parfocal lens is, check this out:
Control
Manual focus system
By default the Canon RF 28-70mm f/2L USM (Amazon, B&H) is set to ‘fly by wire’.
Even though the Canon RF focus ring is technically a ‘focus by wire’ system, the RF lenses are the first line of lenses in the world which have enabled turning focus by wire off.
What is the meaning of focus by wire and fly by wire?
Focus by wire: Let’s say you turn the focus ring to change focus from point A to B. You’d expect the focus to shift accordingly. When you stop point B will be in focus. Now bring the focus point back to A and try again, but at a different speed. Slower or faster, doesn’t matter. Now, even if you precisely rotate to the exact same degree, the focus will not be on point B! The speed of rotation determines which point it is focused on. That’s just completely useless for follow focus work. If an actor or person moves at a different speed, evens lightly, you’ll never get the same focus. Avoid focus by wire lenses like the plague (for video work).
Fly by wire: The distance of focus shifted is directly proportional to the speed at which the ring is turned. This is how a manual focus ring is supposed to operate for video and cinematography.
How to change to fly by wire on RF lenses
You can switch to ‘link to rotational degree’ where the focusing distance will be directly proportional to the rotational degree regardless of the rotational speed.
It is a quick two-step affair that requires you going into the Canon menu and switching the RF manual focus ring sensitivity to ‘linked to rotational degree’ instead of ‘varies with rotational speed’.
This feature will be exceptionally useful for anyone who wants absolute control over the focus ring.
This feature makes an RF lens a game changer for many videographers, filmmakers and cinematographers.
Autofocus system
Dual Pixel Autofocus is, without a doubt, one of the most revered video autofocus systems in the world. Canon claims the new AF actuators will help focusing to be smooth and phantom-quiet.
They have made the motors smaller and smoother with the new Nano USM and Dual Nano USM. The practical application of these new motors can only be judged in real time scenarios.
The dual pixel AF system works better (in theory) than original EF lenses on native EF bodies. I don’t think anyone will be disappointed with its performance.
Zoom Ring
The zoom ring allows you to manually change the focal length from 28mm to 70mm and anywhere in between.
Zoom extension
The Canon RF 28-70mm f/2L USM (Amazon, B&H) does not extend while zooming. That’s great for cinematography, especially when using it with matte boxes and gimbals.
Control System
Canon RF lenses come with an extra customizable ring. See the photo above. The ring is a third ring, in addition to the zoom and focus rings.
This ring is only customizable with cameras that have a native RF mount, such as the Canon EOS R5/6 and Canon EOS C70.
To toggle the Control Ring on and customize it to control one of the exposure determinants, follow these steps:
- Go into Settings
- Go to the Customize dials option
- Select Control Ring and switch it to Enabled.
- Now you can customize it to control aperture, shutter speed, ISO and exposure compensation.
Some videographers will find it helpful in riding the aperture due to its favorable placement right on the lens close to the focus and zoom ring.
Although the turn of the ring appears to be smooth, there is a soft clicking sound. Some might find it inconvenient. If you want to remove the sound you can.
The clicking of the control ring on every RF lens is removable through a chargeable service fee of about $79.99 (depending on your country) at your nearest Canon service center.
Basics
Filter Thread
The Canon RF 28-70mm f/2L USM (Amazon, B&H) has a filter thread diameter of 95mm. This is a very uncommon “large” filter diameter. You’ll probably be using large 4×5.65″ filters with matte boxes. To know more, read this:
Build Quality
The majority of the lens exterior is plastic, though the lens doesn’t feel cheap or fragile.
The optical design consists of 19 elements in 13 groups, including four aspheric elements plus two UD elements and one Super UD element
Size and Weight
The Canon RF 28-70mm f/2L USM (Amazon, B&H) has a diameter of 103.8mm and a length of 139.8mm.
The weight is about 1,430 grams. It is heavy, though I think a lot of video professionals will turn a blind eye to it because there isn’t another zoom like it.
Weather resistance
Canon claims that all RF lenses are weather sealed. This only holds true if the camera body you will be using is also weather sealed. No camera is truly and officially weather sealed, so the best you can hope for is reliable weather resistance.
Canon claims that the RF 28-70mm features dust- and water-resistant construction in the lens mount, switch panel and all rings.
Canon L series lenses have performed well in the past, and I’d be surprised if the RF 28-70mm f/2L can’t match established standards.
What’s in the box
This is what you get in the box (other than the lens):
- Lens cap ( E-95)
- Lens dust cap (D1)
- Bayonet hood (EW-103)
- Drawstring soft pouch (LP1424)
The hood might be useful for photography, but the shape and design makes it mostly vestigial for video work. Some people like to put it on to protect the front element in case of a fall. The hood takes the impact and shatters, but saves the lens.
Alternatives to the Canon RF 28-70mm f/2L IS USM Lens
There isn’t one. Unless prime lenses are okay. You could get four prime lenses for almost the same price of this one lens (with an EF to RF adapter):
- Sigma 24mm f/1.4 Art (B&H, Amazon)
- Sigma 35mm f/1.4 Art (B&H, Amazon)
- Sigma 50mm f/1.4 Art (B&H, Amazon)
- Sigma 85mm f/1.4 Art (B&H, Amazon)
But let’s be honest. If you need a zoom lens you need a zoom lens.
If you are on the fence about either renting or buying the RF 28-70mm f/2L for your next film or project the only alternative you might even consider is the Canon RF 24-70mm f/2.8L IS USM (Amazon, B&H). It is smaller and lighter, has IS, and a wider zoom range. Did I mention cheaper?
I hope you found this overview of the Canon RF 28-70mm f/2L USM (Amazon, B&H) useful. If we have missed out on something, please let us know in the comments below.
