Canon RF Ultrawides Compared

Introduction Comparison Table Executive Summaries

R1 R3 R5 II R5 R5C R6 III R6 II R6 R R8 RP R7 R10 R50 R50V R100

Bodies Compared RF Lenses EF Lenses Flash


10-20mm f/4L IS STM	14-35mm f/4L IS USM	15-35mm f/2.8L IS USM	20mm f/1.4L VCM	15-30mm IS STM	16-28mm f/2.8 IS STM	16mm f/2.8 STM	RF-S 10-18mm IS STM
Full-Frame	Full-Frame	Full-Frame	Full-Frame	Full-Frame	Full-Frame	Full-Frame	APS-C

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March 2025 Better Pictures Canon Reviews RF Lenses EF Lenses Flash All Canon Reviews All Reviews

How to Use Ultrawide Lenses

Introduction top

Introduction Comparison Table Executive Summaries

Long gone are the days when lenses varied in sharpness. All of these lenses are equally ultra-sharp; there is NO significant difference between them. While you can stare at the MTF Curves below until you're blind, and even though you may see some slight differences between them, these differences are invisible to the eye. My tests confirm this; if you're seeing one lens as softer then the other, you're doing something wrong and something other than the lens is affecting the softer picture.

The MTF Curves are at maximum aperture; once you stop down the lenses they become even more similar.

There were Canon's seven mirrorless ultrawides when I wrote this huge page, and a week later Canon announced an eighth ultrawide, the new RF 20mm f/1.4L VCM. It's best for astronomy and low-light action. None of these lenses is good for soft backgrounds. With lenses this wide even f/1.4 doesn't do much to defocus the background. Get any longer lens like the RF 50mm f/1.8 or longer if you want soft backgrounds.

The significant differences are zoom range, maximum aperture, size, weight, cost and whether they have stabilization or other features you want, which is why I have this table:

Comparison Table top

Introduction Comparison Table Executive Summaries

Click any for in-depth reviews

(roughly to scale)
	10-20mm f/4L IS STM	14-35mm f/4L IS USM	15-35mm f/2.8L IS USM	20mm f/1.4L VCM	15-30mm IS STM	16-28mm f/2.8 IS STM	16mm f/2.8 STM	RF-S 10-18mm IS STM
Best for	World's widest pro zoom for the truly demented; there's no way to use a filter to protect the huge and delicate front element.	My favorite ultrawide of all time: largest zoom range of any of these (2.5×), reasonably fast and an L lens at a reasonable price.	The biggest, heaviest, toughest and oldest lens here. Best for full-time pros who beat the heck out of their gear every day.	Fastest lens here by two stops (f/1.4) for astronomy, low light and action.	Lightest and least expensive full-frame zoom for when price and weight matters.	World's lightest f/2.8 ultrawide zoom. Just as sharp as the 15-35mm f/2.8L IS USM for a fraction of the price.	Tiniest f/2.8 ultrawide lens ever. Perfect for ultralight travelers, but lacks IS.	Ultra tiny and high -performance lens for Canon's APS-C cameras. No worries that there's only one for APS-C; this is the perfect lens for these tiny cameras.
Introduced	October 2023	June 2021	August 2019	March 2025	July 2022	January 2025	September 2021	November 2023
Filter Size	Rear Gel ONLY	77mm	82mm	67mm	67mm	67mm	43mm	49mm
Format	Full-Frame	Full-Frame	Full-Frame	Full-Frame	Full-Frame	Full-Frame	Full-Frame	APS-C
Maximum Aperture	f/4	f/4	f/2.8	f/1.4	f/4.5-6.3	f/2.8	f/2.8	f/4.5-6.3
Image Stabilization	Yes	Yes	Yes	no	Yes	Yes	no	Yes
Zoom	Internal (Front & rear groups move in and out, but the barrel never moves)	Pumper	Pumper	(not a zoom)	Pumper	Pumper	none	Pumper
Collapses for Carrying?	no	no	no	no	no	Yes	no	Yes
Close Focus	0.8' 0.25m	0.66' 0.2m	0.92' 0.28m	0.7' 0.2m	0.92' 0.28m	0.66' 0.2m	0.43' 0.13m	0.46' 0.14m
Macro Ratio	0.12×	0.38×	0.21×	0.19×	0.16× (0.52× in a fuzzy trick mode)	0.26×	0.26×	0.23× (0.5× in a fuzzy trick mode)
Diaphragm Blades	9	9	9	11	7	9	7	7
Sunstars	Excellent	Excellent	Excellent	Probably Excellent	Very good	Excellent	Excellent	mild
Sharpness	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent	Excellent
MTF Curves (click to enlarge)
	10-20mm f/4L IS STM	14-35mm f/4L IS USM	15-35mm f/2.8L IS USM	20mm f/1.4L VCM	15-30mm IS STM	16-28mm f/2.8 IS STM	16mm f/2.8 STM	RF-S 10-18mm IS STM
Filter Threads	NONE	Plastic	Plastic	Plastic	Plastic	Plastic	Plastic	Plastic
Barrel Exterior, Controls Rings & Switches	Plastic	Plastic	Plastic	Plastic	Plastic	Plastic	Plastic	Plastic
Interior (seems like)	Plastic & metal	Plastic & some metal	Mainly metal (also the name of my summer music festival)	Plastic & some metal	Plastic & some metal	Plastic & some metal	Plastic	Plastic
Mount	Metal	Metal	Metal	Metal	Metal	Metal	Metal	Plastic
Made in	Japan	Japan	Japan	Probably Japan	Taiwan	Japan	Taiwan	Malaysia
Diameter	3.30" 83.7 mm	3.31" 84.1 mm	3.48" 88.5 mm	3.00" 76.2 mm	3.02" 76.6 mm	3.0" 76.5 mm	2.72" 69.2 mm	2.72" 69 mm
Length (extension from flange)	4.41" 112 mm	3.93" 99.8 mm	4.99" 126.8 mm	3.90" 99.1 mm	3.48" at 30mm (a little longer at 15mm) 88.4 mm at 30mm (a little longer at 15mm)	3.58 ~ 4.44" 91.0 ~ 112.8 mm	1.58" 40.2 mm	1.77" collapsed 44.9 mm collapsed
Weight (actual measured)	19.965 oz. 565.9 g	18.980 oz. 537.9 g	29.405 oz. 833.6 g	18.3 oz. 519 g	13.530 oz. 383.5 g	15.535 oz. 440.4g	5.8 oz. 165 g	5.080 oz. 144.0 g
Price, 3/2025	$2,299	$1,299	$2,199	$1,699	$449	$1,149	$279	$299

Executive Summaries (click any for complete reviews) top

Introduction Comparison Table Executive Summaries

The images below are roughly to scale:

10-20mm f/4L IS STM

Canon RF 10-20mm f/4L IS STM. bigger.

The 10-20mm f/4L IS STM is a lens for the truly insane because it goes far wider than anyone ever really needs, and the price you pay for this luxury is that it's impossible to use any sort of protective filter over the bulbous front element.

Worse, the depth of field is so huge with a lens this wide that any dirt, damage or even fingerprints will probably be visible in your images. The special cap is also pretty crummy, letting in dust if you carry the lens in your pocket as I do.

Therefore it's impractical to carry this lens on your camera around your neck all day. When I shoot it I'm vigilant to keep it capped at all times unless my camera is up to my eye.

The next lens is my favorite; it still goes way wider than anyone needs, and zooms all the way to 35mm and is a very practical and compact lens:

RF 14-35mm f/4L IS USM

Canon RF 14-35mm f/4L IS USM. bigger.

My favorite!

For my style of work, it has the widest and broadest zoom range and macro ratio of all of these, it has L supposed mechanical quality and it's not much bigger or more expensive than any of the others.

I don't need f/2.8; f/4 is more than enough for my nature and landscapes.

RF 15-35mm f/2.8L IS USM

Canon RF 15-35mm f/2.8L IS USM. bigger.

This beast is the oldest, biggest, heaviest and most expensive of all of these — but not sharper.

This is Canon's first RF ultrawide. The newest 16-28mm f/2.8 IS STM is just as fast, has equally great stabilization and sunstars, and even closer close-focus — with half the weight and cost.

The RF 15-35mm f/2.8L IS USM is the toughest lens here and is a great choice for the full-time pro who beats on his gear all day, every day.

RF 20mm f/1.4L VCM

Canon RF 20mm f/1.4L VCM. bigger.

New as of 2025, this is the fastest lens here, with at least two stops (four times) the light gathering power of any of the other lenses.

This lens is for astronomers and people who work in extremely low light, or people who need to stop action in regular low light.

It is not for getting soft backgrounds; focal length is far more important for that than f/stop; even the inexpensive RF 50mm f/1.8 STM will give much softer backgrounds than this lens.

This f/1.4 lens is all about gathering lots of light so we can shoot at lower ISOs for cleaner images or with shorter exposure times so we can spend less time freezing out in the dark shooting the Milky Way, or use shorter exposure times for action which image stabilization cannot stop. This lens has no image stabilization

RF 15-30mm f/4.5-6.3 IS STM

Canon RF 15-30mm f/4.5-6.3 IS STM. bigger.

The smallest, lightest and least expensive full-frame zoom here, and it's just as sharp and stabilized for less than half the price of the other full-frame zooms, but it's one or two stops slower than all the other lenses here.

I easily can hand-hold it at night, so if you don't mind the slower speed, by all means this baby takes exactly the same pictures as the others.

If money matters and you're not shooting every day, by all means get this lens. See also Is It Worth It.

RF 16-28mm f/2.8 IS STM

Canon RF 16-28mm f/2.8 IS STM. bigger.

Compact, inexpensive, fast and ultralight, but has the most restricted zoom range. This restricted zoom range is why it can be just as sharp as the others, but smaller, lighter and less expensive at the same time.

If you're trying to keep weight and expense to a minimum and need a fast, stabilized f/2.8, this is your lens.

RF 16mm f/2.8 STM

Canon RF 16mm f/2.8 STM. bigger.

This unique little ultrasharp gem is about the size of a rear lens cap and can create astounding images.

It's also nearly free, but has no stabilization and doesn't zoom. So? I have hands of iron and easily can handhold it at night, and I don't need it to zoom; I just pop on my 24-xx zoom when I need longer.

All of these zooms duplicate the wide end of a normal zoom, so do you really want to carry the extra weight? See also Assembling a System.

This lens is for people on the strictest weight or cost budget — with no loss in image quality. If you rarely need an ultrawide or appreciate The Joy of Carrying Less, this is the perfect stocking stuffer to pop in a side pocket of your camera bag or jacket.

RF-S 10-18mm IS STM (APS-C ONLY)

Canon RF-S 10-18mm IS STM. bigger.

This tiny lens is only for APS-C cameras, which as of March 2025 are the R7, R10, R50 and R100 (see these cameras compared).

This lens isn't comparable to any of the others because it's for a completely different format.

The other lenses become normal lenses and therefore are a waste of a good lens and your money on APS-C.

Likewise, don't use this 10-18mm on a full-frame camera because while it will seem to work OK, what you may not realize until you look at the pixel dimensions of your images is that your full frame camera automatically threw away most of the pixels and sensor area, using only the central APS-C portion and blowing it up to look normal in your finder. Only use this on full-frame in an emergency.

If you have an APS-C camera, this 10-18mm is your only choice for an ultrawide, and an excellent one.

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25 mar 2025 add 20/1.4, 17 Mar add 10-20mm, 13 March 2025