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Canon RF 45mm f/1.2 STM

Ultralight & Ultrafast: $469!!! (2025 ~ today)

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Bodies Compared  RF Lenses  EF Lenses  Flash

Canon RF 45mm f/1.2 STM (67mm filters, 12.2 oz./346g, 1.5'/0.45m close focus, 0.13× macro ratio, just $469). bigger. I got mine from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

This 100% all-content, junk-free website's biggest source of support is when you use those or any of these links to my personally approved sources I've used myself for way over 100 combined years when you get anything, regardless of the country in which you live. Canon does not seal its boxes in any way, so never buy at retail or any other source not on my personally approved list since you'll have no way of knowing if you're missing accessories, getting a defective, damaged, returned, gray-market, store demo or used lens — and all of my personally approved sources allow for 100% cash-back returns for at least 30 days if you don't love your new lens. I've used many of these stores since the 1970s because I can try it in my own hands and return it if I don't love it, and because they ship from secure remote warehouses where no one gets to touch your new lens before you do. Buy only from the approved sources I've used myself for decades for the best prices, service, return policies and selection.

February 2026   Better Pictures   Canon Reviews   RF Lenses   EF Lenses   Flash   All Canon Reviews   All Reviews

RF 50mm f/1.4L VCM

RF 50mm f/1.2L USM

RF 35mm f/1.8 Macro IS STM

RF 35mm f/1.4L VCM

EF 35mm f/1.4L II (2015-today, 72mm filters, 26.8 oz./760 g, 0.92'/0.28m close focus, 0.21× macro ratio, works great on an EF-to RF adapter).

EF 35mm f/1.4L (1998-2015, metal 72mm filter thread, 20.5 oz./582 g, 1'/0.3m close focus, 0.18× macro ratio, works great on an EF-to RF adapter).

Sony vs. Nikon vs. Canon Full-Frame

Why Fixed Lenses Take Better Pictures

Sample Images       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

More samples throughout this review at Bokeh, Coma, Falloff, Macro, Spherochromatism and Sunstars.

These are just snapshots; my real work is in my Gallery.

These are all shot hand-held as NORMAL (▟ stairstep icon) JPGs; no tripods, FINE ( quarter-circle icon) JPGs or RAW CR3 files were used or needed.

Red and Green Number Five in a Parking Structure at Ryan's college, 3:10 PM, Tuesday, 13 January 2026. Canon EOS R6 III in square-crop mode, Canon RF 45mm f/1.2 STM at f/5.6 handheld at ¹/₁₀ at Auto ISO 200 (LV 7.4), Radiant Photo software to add light. bigger or full-resolution 4,640 × 4,640 pixel © 8 MB image.

Ryan giving us the walking tour of the routes to and from his classes for next semester at college, 3:40 PM, Tuesday, 13 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/5.6 at ¹/₁₆₀ at Auto ISO 100, +0.7 stops exposure compensation (LV 12.4), cropped to about a square and otherwise exactly as shot. bigger.

Ryan in the Porsche coming home from school, 5:16 PM, Tuesday, 13 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/1.2 handheld at ¹/₁₅ at Auto ISO 100, +0.7 stops exposure compensation (LV 4.6), Radiant Photo software. bigger or full-resolution 32 MP © 3.3 MB JPG.

Bokeh!, and it's very sharp off on the sides, and my R6 III easily focussed way out there on the right. Not bad for $469; back in previous decades this level of f/1.2 aspherical performance cost thousands and thousands of dollars.

B&W Matrix 805 Sixth-Order Loudspeaker on a pair of Audioengine DS1 Stands Sitting on My Desk, 8:30 AM, Saturday, 10 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/1.2 at ¹/₂₅ at Auto ISO 100 (LV 5¼), Radiant Photo software. bigger or camera-original 32 MP © 7 MB JPG.

See how the in-focus part of the grill cloth and the solid-alloy B&W MATRIX badge stand out from everything else? This three-dimensional look comes from this lens' combination of super sharpness where it's in focus and super-soft bokeh where it's not.

Of course stopped-down for normal shooting it's always ultra-sharp:

Orange Porsche 911, 10:05 AM, Saturday, 10 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/8 at ¹/₅₀₀ at Auto ISO 100 (LV 15.0), Radiant Photo software. bigger or camera-original 32 MP © 5.5 MB JPG.

Introduction       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

B&H Photo - Video - Pro Audio I buy only from these approved sources. I can't vouch for ads below.

This Canon RF 45mm f/1.2 STM is the world's first inexpensive name-brand f/1.2 normal lens.

The first f/1.2 aspherical lenses cost five figures when they were introduced as ultra-exotics in 1966. This new lens is extraordinary in that it offers superb bokeh and high sharpness at a price we all can afford.

This lens has far superior performance to historical f/1.2 lenses like the old Nikon 58mm f/1.2 NOCT (1977~1997). It has far better bokeh and far superior sharpness at every aperture than the old 58mm f/1.2 NOCT.

This 45mm f/1.2's optics are superior to historical f/1.2 lenses and even somewhat better than the current EF 50mm f/1.2L USM that came out in 2006.

For astronomy, science and pixel counters the newest RF 50mm f/1.2L USM offers superior performance in the lab for over five times the price, while this 45mm f/1.2 offers carefully controlled aberrations that many prefer for giving our images more character than the RF 50mm f/1.2L. If you're doing astronomy then get the RF 50mm f/1.2L USM; if you want amazing bokeh and similar effects then get this 45mm f/1.2 instead and laugh all the way to the bank.

Focal lengths from 40mm to 45mm have always been considered the Perfect Normal because they have the same focal length as the diagonal of the image sensor. These have been appreciated for almost 200 years as representing the most normal angle of view — not 50mm lenses.

While 50mm lenses often are just a little too long for many subjects and 35mm lenses often are just a little too wide, a 45mm lens is almost always the Perfect Normal.

This is a superb choice as an ultra-fast Perfect Normal lens. It's also ultralight, weighing 40% less than the already lightweight RF 35/1.4L VCM and RF 50mm f/1.4L VCM, and costs less than one-third as much!

This lens' only limitations are that it doesn't focus quite as close as other lenses (an optical trick that helps Canon keep the cost down), it has no optical stabilization (nor do any other RF f/1.2 or f/1.4 lenses and these all work great with in-camera stabilization if you have it), and it does have more coma than the more exotic RF L lenses if you care. It certainly has superior performance to any FD or EF lens.

It becomes a short telephoto on APS-C.

I love that it has a dedicated AF/MF switch.

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

New       intro       top

The world's first discount camera-brand f/1.2 lens — ever.

Canon's first fixed 45mm lens dedicated to the EOS R mirrorless system.

Good       intro       top

Sharp.

Superb bokeh.

Second programmable control ring.

AF/MF switch.

Small.

Light.

Almost free.

100% U.S.A.-based high-quality technical support at (800) OK-CANON.

Bad       intro       top

Plastic filter threads and plastic exterior - like everything today.

Soft plastic filter threads are easy to cross thread, typical of consumer lenses in 2025.

Missing       intro       top

No Image Stabilization.

No Stabilizer switch for in-camera stabilization.

Mounting index dot not raised so it can't be found by feel in the dark.

No focus or depth-of-field scales.

No infra-red focus indices.

Only stops down to f/16.

Canon RF 45mm f/1.2 STM. bigger.

Specifications       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

Compatibility

This lens only works on Canon's EOS-R series of mirrorless cameras.

It won't work with any teleconverters, EF or either of the RF 2× Extender or RF 1.4× Extender teleconverters.

It won't fit on, and cannot be adapted to, any DSLR because a DSLR has too much distance between its sensor and its lens mount flange.

Name       specifications       top

Canon calls this the RF 45mm f/1.2 STM:

    RF: Works only on Canon's EOS-R Mirrorless cameras.

    STM: STepper (focus) Motor.

Canon's Model Number: RF4512STM.

Optics       specifications       top

Canon RF 45mm f/1.2 STM Internal Optical Construction. Aspherical element.

9 elements in 7 groups.

1 plastic molded Aspherical ("PMo") element. Not to worry, molded plastic aspherical elements have been huge helps in increasing image quality since about year 2000.

Highly evolved Double-Gauss design.

The front and many other elements behind it motor in and out together while the rear element(s) stays fixed. The outer barrel doesn't move; the elements move in and out protected by the barrel. yes, the front element moves as seen from the front of the lens; use a filter if you're worried about that.

Super Spectra multicoating.

Diaphragm       specifications       top

Canon RF 45mm f/1.2 STM. bigger.

9 rounded blades.

Electronically actuated.

Stops down to f/16.

Filters       specifications       top

Plastic 67mm filter thread.

Coverage       specifications       top

Full frame and APS-C.

Focal Length       specifications       top

45mm, the Perfect Normal lens.

When used on APS-C, it sees the same angle of view as a 72 mm lens sees when used on a full-frame or 35mm camera.

See also Crop Factor.

Angles of View on Full Frame       specifications       top

51° 20' diagonal.

43° 35' horizontal.

29° 50' vertical.

Focus Scale       specifications       top

No.

Not on lens, but may be displayed in-camera.

Infinity Focus Stop       specifications       top

No.

You have to focus somehow to get precise focus at infinity, just like at every other distance.

Depth of Field Scale       specifications       top

No.

Not on lens, but may be displayed in-camera.

Infrared Focus Index       specifications       top

No.

Close Focus (distance from subject to image plane)       specifications       top

1.5 feet (0.45 meters).

Maximum Reproduction Ratio       specifications       top

1:7.7 (0.13×).

Minimum Subject Field       specifications       top

10.90 × 7.27 inches (277 × 185mm).

Image Stabilizer       specifications       top

NONE, and works great with in-camera stabilization if you have it.

Caps       specifications       top

Canon E-67II 67mm front cap.

Rear Lens Dust Cap RF (p/n 2962C001).

Hood       specifications       top

Optional ES-73B hood for the 45mm f/1.2 (also at Adorama).

Case       specifications       top

None included.

Size       specifications       top

3.07" ø maximum diameter × 2.95" extension from flange.

78 mm ø maximum diameter × 75 mm extension from flange.

Weight       specifications       top

12.2 oz. (346 g).

Announced       specifications       top

1:17 AM, Thursday, 06 November 2025, NYC time.

Promised for       specifications       top

December 2025.

Included       specifications       top

Lens.

Canon E-67II 67mm front cap.

Rear Lens Dust Cap RF (p/n 2962C001).

Canon's Model Numbers       specifications       top

Model number: RF4512STM.

Product code: 7198C002 (7198C001 in Japan).

JAN code: 4549292-248982.

Price, U. S. A.       specifications       top

10 February 2026

$469 at B&H, at Adorama, at Crutchfield and at Amazon.

About $400 used if you know How to Win at eBay.

November 2025 (Announcement)

$469 at B&H and at Adorama.

Accessories       top

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Specifications   Accessories   USA Version

Performance   Compared   Recommendations

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

ES-73B hood for the 45mm f/1.2 (also at Adorama).

67mm filters.

Getting a Legal U. S. A. Version       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

This section applies in the U. S. A. only.

Your lens must include a printed U. S. A. warranty card from Canon U.S.A., Inc. It should be on top inside your box as you open it. The serial number on the card must match the serial number on the bottom of your lens for the warranty to be valid, and you must have purchased it from an authorized (by Canon USA) dealer.

If you have no card or the serial number doesn't match, you got ripped off with a gray market version intended to be sold in another country. This is why I never buy from any place other than my personally approved sources. You just can't take the chance of buying elsewhere, especially at any retail store where strangers have probably opened your completely unsealed box and played with your camera, because non-U. S. A. versions have no warranty in the U. S. A., and you probably won't be able to get firmware or service for it — even if you're willing to pay out-of-pocket for it when you need it!

Shifty dealers may include color copies of a card from a legitimate U. S. A. product in a gray-market box, hoping you won't check serial numbers and catch their fraud. A card with the wrong serial number means nothing other than that you have no warranty coverage.

The serial number on the box on the bottom right of the top UPC doesn't have to match, but it should. If not, it means a shady dealer took things out of boxes and was too sloppy to put them back correctly — and it means you got a used lens if anyone other than you took it out of the box.

If a gray market version saves you $200 the risk might be worth it, but for $200 or less I wouldn't risk having no warranty or support.

Always be sure to check yours while you can still return it, or just don't buy from unapproved sources and never at retail so you'll be able to have your camera serviced and get free updated firmware as needed. Get yours from the same places I do and you won't have a problem.

Performance       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

Overall   Autofocus   Manual Focus   Breathing

Distance Recording   Bokeh   Coma   Distortion

Ergonomics   Falloff   Filters   Flare & Ghosts

Lateral Color Fringes   Lens Corrections   Macro

Mechanics   Sharpness   Spherochromatism

Stabilization   Sunstars   Teleconverters

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

Overall       performance       top

This lens performs in ways that no sub-$500 lens ever has. It has better performance than every classic f/1.2 lens as well as better than the EF 50mm f/1.2L.

While it can get a tiny bit softer in the far corners at f/1.2 if you look too hard, it is precisely this character which endears it to many serious users. Pixel counters rarely, if ever, create any compelling photographs.

Autofocus       performance       top

Autofocus is always dead-on, especially at f/1.2 where it's critical. The days of spherical-aberration induced focus offsets and errors we saw in DSLRs, which used entirely different AF systems, are gone. Whatever may be happening, Canon has ensured focus is flawless so we can get all the sharpness this lens can give. This is typical with mirrorless camera, which read focus directly off the image sensor compared to DSLRs which read focus off a separate AF sensor buried in the base of the camera and were connected quite literally by a weird chain of mirrors.

Autofocus is fast enough.

Ultraspeed lenses usually take longer to focus to allow the precision required for perfect focus at f/1.2, and considering how slowly most f/1.2 lenses autofocus, this lens actually focuses pretty fast.

Manual Focus       performance       top

Manual focusing is entirely electronic; the manual focus ring isn't connected to anything other than a digital encoder.

There is an AF/MF switch, thank goodness.

No matter what you do, all Canon EOS-R cameras as of February 2026 in SERVO AF mode will continue to autofocus as soon as you stop turning the manual focus ring. Sadly only Nikon has this all figured out today.

Focus Breathing       performance       top

Focus breathing is the image changing size (growing and shrinking slightly) as focused in and out. It's important to cinematographers that the image not breathe (change size) as focus gets pulled back and forth between different actors as they speak. The image is said to breathe because it expands and contracts as the focus follows the dialog back and forth.

Since most of the elements move out to focus closer, the image grows as focussed more closely.

Focus Distance Recording       performance       top

The focused distance is recorded in the EXIF data.

I read this in the lower left of my screen in Photoshop's lens correction filter.

Bokeh       performance       top

Bokeh, the feel, character or quality of out-of-focus areas as opposed to how far out of focus they are, is superb. Backgrounds simply disappear!

Here are photos from headshot distance. I'm focused on the DAVIS logo. Click any for the © camera-original file:

Made-in-U. S. A. Davis 6357 Vantage Vue Wireless Sensor Suite (use with WeatherLink console), 9:08 AM, Thursday, 12 February 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM with Made-in-U. S. A. Tiffen ND 0.9 (3 stop) neutral density filter at ¹/_2,500, ¹/_1,000 and ¹/₂₅₀ at Auto ISO 100. +1 stop exposure compensation (LV 12.0, 12.0 and 12.0). Click any for the 32 MP © camera-original JPG files.

Here are shots showing blur circles. I'm focused on the turtle head on the lower right at about one meter (three feet) while my Christmas tree is at about 3 meters (ten feet) away. Click any for the © camera-original file:

Rockwell's Christmas Tree, Sunday, 11 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at ¹/₁₀₀, ¹/₄₀, ¹/₂₀ and ¹/₁₀ at Auto ISO 100 (LV 7¼, 6.4, 6.4 and 6.4), exactly as shot. Click any for the 32 MP © camera-original JPG file.

These are great, even blur circles. Even stopped down at the larger aperture they remain circular. I do see some slight "onion ring" effects due to how the aspherical element is manufactured, but you won't see this in any real photo of anything other than out-of-focus point sources.

As always, if you want to throw the background as far out of focus as possible, shoot at f/1.2 and get as close as possible.

Coma       performance       top

Coma, or sagittal coma flare, is often seen at large apertures with fast normal to wide lenses as weird batwing shapes on bright points of light in the corners at night. They go away as stopped down.

As expected for a largely double-Gauss design, we have some coma wide-open f/1.2. This is this lens' biggest optical flaw, which is usually completely invisible unless you go out of your way looking for it by putting point-sources in the far corners and then shoot wide-open at f/1.2.

Wide-Open at f/1.2

Coma isn't that bad, and this is worst case. Notice how of course very bright sources of light will generate visible coma, while normal subjects like stars aren't as bright and cause no problems.

Nacht, 6:15 PM Saturday, 10 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/1.2 for 10 seconds at ISO 100 (LV -2¾, or minus 2¾!), Radiant Photo software to add light. bigger, full-resolution image or 32 MP © camera-original 4.9 MB JPG file.

1,200 × 900 pixel (5.8× magnification) crop from the lower right of the above image. bigger, full-resolution image or 32 MP © camera-original 4.9 MB JPG file.

If this 1,200 × 900 pixel crop is about 3" (8cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 12 × 18" (30 × 45 cm).

If this 1,200 × 900 pixel crop is about 6" (15cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 23 × 35" (59 × 89 cm).

If this 1,200 × 900 pixel crop is about 12" (30cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 47 × 70" (119 × 178 cm).

At f/2.5

Coma goes away quickly when stopped down, as expected:

Nacht, 6:25 PM Saturday, 10 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/2.5 for 30 seconds at ISO 100 (LV -2.4, or minus 2.4!), Radiant Photo software to add light. bigger, full-resolution image or 32 MP © camera-original 4.9 MB JPG file.

1,200 × 900 pixel (5.8× magnification) crop from the lower right of the above image. bigger, full-resolution image or 32 MP © camera-original 5.1 MB JPG file.

If this 1,200 × 900 pixel crop is about 3" (8cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 12 × 18" (30 × 45 cm).

If this 1,200 × 900 pixel crop is about 6" (15cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 23 × 35" (59 × 89 cm).

If this 1,200 × 900 pixel crop is about 12" (30cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 47 × 70" (119 × 178 cm).

Distortion       performance       top

This lens utilizes electronic distortion correction as part of its optical design, therefor in-camera distortion correction cannot be turned off.

In-camera correction does a great job, with no measurable or visible distortion.

If you shoot raw data rather than JPG images, whatever software you use to create visible images from raw data may or may not correct the distortion as is done in-camera as JPGs. You're on your own there; I don't bother with raw data.

Ergonomics       performance       top

This lens is easy to shoot.

It's the perfect size, it has a big rubbery focus ring and a smaller programmable knurled clicked ring in front of the focus ring.

The AF/MF switch is very helpful.

Falloff       performance       top

Falloff on full-frame isn't visible in normal shooting with the default lens falloff correction left ON.

I've greatly exaggerated the falloff by shooting a gray field and placing these on a gray background; it will not look this bad in actual photos of real things:

Falloff on full-frame at infinity, Peripheral Illumination correction at its default of ON: f/1.2 f/1.4 f/2 f/2.8 © 2026 KenRockwell.com. All rights reserved.

If you save only raw data rather than create JPG images in-camera, whatever software you use to create visible images from that raw data later may or may not correct this as is done in-camera as JPGs. You're on your own there; I don't bother with raw data.

If you go out of your way to turn off the correction, or possibly in some raw software, this is what you get:

Falloff on full-frame at infinity, Peripheral Illumination correction deliberately turned OFF: f/1.2 f/1.4 f/2 f/2.8 © 2026 KenRockwell.com. All rights reserved.

Without correction it probably will be visible at f/1.2 in normal photographs.

Filters, use with       performance       top

There's no need for thin filters. I can use quite a stack of several standard 67mm filters with no vignetting at any setting on full-frame.

Go ahead and use your standard rotating polarizer and grad filters.

Flare & Ghosts       performance       top

It's has a bit more ghosts than most other lenses, which many people may find quite compelling for adding character.

See examples at Sunstars.

Lateral Color Fringes       performance       top

There are no lateral color fringes when shot as JPG with the default Chromatic Aberration Correction left ON.

if you go out of your way to turn this OFF (or shoot raw and then use non-manufacturer software to process that data into images) then there is a just about invisible amount of green/magenta fringing. I'm very impressed, even with no correction there is essentially no lateral color, which is superb performance.

There is spherochromatism, which can cause color fringes on things that aren't in perfect focus at large apertures. Spherochromatism is a completely different aberration in a different dimension than lateral color fringes.

Lens Corrections       performance       top

Other cameras may vary as the years roll on, but my EOS R1, R3, R5 II, R5, R6 III, R6 II, R6, R, R8, RP, R7, R10, R50 and R100 all have options to correct for falloff (Peripheral Illumination Correction), Distortion and a Digital Lens Optimizer which corrects for a suite of other aberrations.

These are all ON by default.

This lens integrates electronic distortion correction as part of its design, so the Distortion setting is grayed-out because it can not be turned off.

You can turn off falloff correction and/or the Digital Lens Optimizer.

If you turn off the Digital Lens Optimizer, you are then offered à la carte ON/OFF options for Chromatic Aberration Correction and Diffraction Correction.

If you shoot raw data rather than JPG images, whatever software you use to create visible images from raw data may or may not correct these as is done in-camera as JPGs. You're on your own there; I don't bother with raw data.

Macro Performance       performance       top

This lens doesn't get very close by modern standards, only to 1.5' (0.45 meters) or a 0.13× macro ratio.

If you prefer a fast, fixed lens that also focuses ultra-close, then opt for the RF 35mm f/1.8 Macro IS STM instead, and also adds optical stabilization.

Wide-Open at f/1.2

While it doesn't get that close, it is surprisingly sharp this close:

Casio G-Shock Solar Atomic Watch at close-focus distance, 1:15 PM Monday, 19 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/1.2 at ¹/_6,400 at ISO 50 (L), +0.7 stops exposure compensation (LV 14¼). bigger or camera-original 32 MP © 4 MB JPG.

It is surprisingly sharp for a lens this fast and this close at f/1.2, and as expected spherochromatism creates magenta and green fringes on out-of-focus highlights:

1,200 × 900 pixel (5.8× magnification) crop from above. bigger or camera-original 32 MP © 4 MB JPG.

If this 1,200 × 900 pixel crop is about 3" (8cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 12 × 18" (30 × 45 cm).

If this 1,200 × 900 pixel crop is about 6" (15cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 23 × 35" (59 × 89 cm).

If this 1,200 × 900 pixel crop is about 12" (30cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 47 × 70" (119 × 178 cm).

At f/8

Like all lenses, it's super-sharp at f/8:

Casio G-Shock Solar Atomic Watch at close-focus distance, 1:16 PM Monday, 19 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/8 at ¹/₃₂₀ at ISO 100, +0.7 stops exposure compensation (LV 14.4). bigger or camera-original 32 MP © 6.1 MB JPG.

It is surprisingly sharp for a lens this fast and this close at f/1.2, and as expected spherochromatism creates magenta and green fringes on out-of-focus highlights:

1,200 × 900 pixel (5.8× magnification) crop from above. bigger or camera-original 32 MP © 6.1 MB JPG.

If this 1,200 × 900 pixel crop is about 3" (8cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 12 × 18" (30 × 45 cm).

If this 1,200 × 900 pixel crop is about 6" (15cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 23 × 35" (59 × 89 cm).

If this 1,200 × 900 pixel crop is about 12" (30cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 47 × 70" (119 × 178 cm).

Mechanical Quality       performance       top

Canon RF 45mm f/1.2 STM. bigger.

It's the usual for 2026: almost all plastic on the outside, with a metal mount.

Exterior Finish

Black plastic.

Front Bumper

None.

Filter Threads

Plastic.

Hood Bayonet Mount

Plastic.

Front Programmable Control Ring

Hard plastic.

Focus Ring

Rubber-like ribs.

Slide Switch

Plastic.

Identity

Printed around front of lens barrel, also "45" printed on top of barrel.

Internals

Seem like mostly plastic.

Dust Gasket at Mount

No. So?

Mount

Chromed metal.

Markings

Just paint; nothing's engraved.

Serial Number

Canon RF 45mm f/1.2 STM. bigger.

Laser engraved in warm black on black on the bottom of the barrel.

It's almost completely invisible in actual use; it's visible above because this photo is enlarged and lit by lots of light in my studio.

Date Code

The serial number contains a date code.

My serial number starts with 156, which means it was made in August 2025.

Noises When Shaken

Moderate clunking.

Made in

Canon RF 45mm f/1.2 STM. bigger.

Made in Malaysia.

Sharpness       performance       top

Lens sharpness has nothing to do with picture sharpness.

Every lens made in the past 100 years is more than sharp enough to make super-sharp pictures if you know what you're doing. The only limitation to picture sharpness is your skill as a photographer. It's the least talented who spend the most time worrying about lens sharpness and blame crummy pictures on their equipment rather than themselves. Skilled photographers make great images with whatever camera is in their hands; I've made some of my best images of all time with an irreparably broken camera! Most pixels are thrown away before you see them, but camera makers don't want you to know that.

If you're not getting ultra-sharp pictures with this, be sure not to shoot at f/11 or smaller where all lenses are softer due to diffraction, always shoot at ISO 100 or below because cameras become softer at ISO 200 and above, avoid shooting across long distances over land which can lead to atmospheric heat shimmer, be sure everything is in perfect focus, set your camera's sharpening as you want it (I set mine to the maximum of 7,1,1) and be sure nothing is moving, either camera or subject. If you want to ensure a soft image with any lens, shoot at f/16 or smaller at ISO 1,600 or above at default sharpening in daylight of subjects at differing distances in the same image.

People worry waaaaay too much about lens sharpness. It's not 1968 anymore when lenses often weren't that sharp and there could be significant differences among them; ever since about 2010 all new lenses are all pretty much equally fantastic.

This lens is super sharp at every aperture, although the corners at f/1.2 can have less contrast due to coma. If you're counting pixels, stop down to f/8 for the sharpest corners — but that's not why you buy this lens. Your images will be more limited by your vision as an artist and by diffraction than by this lens.

Used properly, all of Canon's RF lenses are equally sharp. The differences are in maximum apertures and focal lengths, but none of them are soft if you know how to use them. Lens sharpness has nothing to do with picture sharpness.

MTF wide-open at f/1.2 at 10 cyc/mm (black) and 30 cyc/mm (blue). Sagittal (solid) and meridional (dashed).

While it's usually valid to compare rated MTFs between different lenses of similar vintage from the same maker, every maker measures or simply calculates MTF very differently, and therefore one cannot compare these curves between brands. For instance, Sony seems to ignore diffraction and simply calculate overly optimistic MTFs that hug 100%, which no real lens can do at f/8, while other brands are more realistic and include diffraction. Only Canon offers any insight on how they arrive at their curves.

See also my article on MTF and Canon's article on MTFs.

Spherochromatism       performance       top

Spherochromatism, also called secondary spherical chromatic aberration or "color bokeh," is an advanced form of spherical and chromatic aberration in a different dimension than lateral chromatic aberration and therefore cannot be corrected with software or automatic corrections. It happens mostly in fast normal and tele lenses when spherical aberration at the ends of the color spectrum (red and blue) are corrected differently than in the middle of the spectrum (green).

Spherochromatism can cause colored fringes on out-of-focus highlights, usually seen as green fringes (the middle of the spectrum) on background highlights and magenta fringes (the red and blue ends of the spectrum added together make magenta) on foreground highlights.

Spherochromatism is common in fast lenses of moderate focal length when shooting contrasty items at full aperture. It goes away as stopped down.

Spherochromatism is a completely different aberration from lateral color fringes.

This 45mm f/1,2 has a healthy amount of spherochromatism, with classic green fringes behind and magenta fringes ahead of the plane of perfect focus:

Mondaine A132.30348.11SBB at close-focus distance, 1:18 PM Monday, 19 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/1.2 at ¹/_1,250 at ISO 100, +1.3 stops exposure compensation (LV 11.0). bigger or camera-original 32 MP © 3.7 MB JPG.

1,200 × 900 pixel (5.8× magnification) crop from above. bigger or camera-original 32 MP © 3.7 MB JPG.

If this 1,200 × 900 pixel crop is about 3" (8cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 12 × 18" (30 × 45 cm).

If this 1,200 × 900 pixel crop is about 6" (15cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 23 × 35" (59 × 89 cm).

If this 1,200 × 900 pixel crop is about 12" (30cm) wide on your screen, then the complete image printed at this same extreme magnification would be about 47 × 70" (119 × 178 cm).

Image Stabilization (IS)       performance       top

This lens has no Optical Image Stabilization (OIS, IS or VR (Vibration Reduction)), however it works magnificently with in-camera stabilization.

"Percent Perfectly Sharp Shots" are the percentage of hand-held, free-standing with no support or bracing, frames with 100% perfect tripod-equivalent sharpness as viewed at 300%. Hand tremor is a random occurrence, so at marginal speeds some frames will be perfectly sharp while others will be in various stages of blur — all at the same shutter speed.

This rates what percentage of shots are perfectly sharp, not how sharp are all the frames:

I see SIX stops of real-world improvement!!!

I set the Minimum Shutter Speed in Auto ISO in my EOS R6 III to Auto Slow -3. While I could set a fixed speed of ⅛ rather than letting Auto select the same ⅛, it wouldn't magically change when I swapped to other lenses as it will in Auto.

Sunstars       performance       top

Chrome Bumper Sunstars, 11:49 AM, Saturday, 10 January 2026. Canon EOS R6 III, Canon RF 45mm f/1.2 STM at f/16 at ¹/₆₀ at Auto ISO 100 (LV 14.0), Radiant Photo software. bigger.

With a 9-bladed rounded diaphragm, I get mild 18-point sunstars on brilliant points of light, mostly at the smallest apertures.

Ignore the vertical smear at large apertures. This is a sensor artifact called interline transfer smear and is a camera, not a lens, defect.

Likewise ignore the crazy rainbow dots at small apertures; these are sensor artifacts caused by interference among the divisions between pixels on the sensor. These are made visible because we're using enough exposure to show the dark underside of a huge palm tree, and then putting the blinding disk of the mid-day sun in it. Doing this will show everything due to the insane lighting range.

Click any to enlarge:

Click any to enlarge.

Teleconverters       performance       top

This lens does not work with any teleconverters

There is not enough room in the back of the lens to accommodate the protuberances from either of the Canon RF 1.4× or Canon RF 2× extenders.

Compared       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

This 45mm f/1.2's optics are superior to historical f/1.2 lenses and even somewhat better than the current EF 50mm f/1.2L USM that came out in 2006.

This lens has far superior performance to the old Nikon 58mm f/1.2 NOCT (1977~1997), with far better bokeh and far superior sharpness at every aperture than the old 58mm f/1.2 NOCT.

For astronomy, science and pixel counters the newest RF 50mm f/1.2L USM offers superior performance in the lab for over five times the price, while this 45mm f/1.2 offers carefully controlled aberrations that many prefer for giving our images more character than the RF 50mm f/1.2L. If you're doing astronomy then get the RF 50mm f/1.2L USM; if you want amazing bokeh and similar effects then get this 45mm f/1.2 instead and laugh all the way to the bank.

This lens' only limitations are that it doesn't focus quite as close as other lenses (an optical trick that helps Canon keep the cost down), it has no optical stabilization (nor do any other RF f/1.2 or f/1.4 lenses, and these all work great with in-camera stabilization if you have it), and it does have more coma than the more exotic RF L lenses if you care. It certainly has superior performance to any FD or EF lens.

Compared to Other RF Lenses

1.) Use with EF to RF adapter on mirrorless cameras.

2.) With in-camera correction.

3.) Measured with EF to RF Ring adapter for modern mirrorless cameras.

4.) If you know How to Win at eBay.

Compared to Canon EF Lenses

1.) Use with EF to RF adapter on mirrorless cameras.

2.) With in-camera correction.

3.) Measured with EF to RF Ring adapter for modern mirrorless cameras.

4.) If you know How to Win at eBay.

Compared to Nikon       compared       top

Of course comparing to Nikon is silly; none of thee Nikon lenses will fit your Canon camera.

* If you know How to Win at eBay.

Recommendations       top

Sample Images   Intro   New   Good   Bad   Missing

Specifications   Accessories   USA Version

Performance   Compared   Recommendations

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

This is a very handy lens for many things. While I prefer the RF 24-240mm IS USM for its huge zoom range for most of my shooting, for low-light action and astronomy this lens gives the budget-conscious an option that the world has never seen before: an affordable modern autofocus f/1.2 lens from a major camera maker!

I use a clear (UV) protective filter instead of a cap (exactly like an iPhone) so I'm always ready to shoot instantly. I only use a cap when I throw this in a bag with other gear without padding — which is never. The UV filter never gets in the way, and never gets lost, either.

The very best protective filter is the nearly indestructible Hoya multicoated HD3 67mm UV which uses hardened glass and repels dirt and fingerprints.

For less money, the Nikon 67mm NC (No Color/Neutral Clear), Hoya 67mm NXT Plus UV and Hoya 67mm UV MC are all excellent filters, but the Hoya HD3 is the toughest and the best.

If I was working in nasty, dirty areas, I'd use an uncoated 67mm Tiffen UV filter instead. Uncoated filters are much easier to clean, but more prone to ghosting.

Filters last a lifetime, so you may as well get the best. The Hoya HD3 stays cleaner than the others since it repels oil and dirt.

You may need a neutral-density filter to shoot at f/1.2 in direct sunlight. I prefer the Made-in-U. S. A. Tiffen 67mm ND 0.9 (3 stop) neutral density filter because the glass Tiffen filters are genuinely neutral, devoid of the color casts I often find in other brands who sometimes resin (plastic) filter materials.

You could try a 67mm polarizing filter to shoot at f/1.2 in daylight (my very favorite is the exquisitely well made Nikon Circular Polarizer II), however polarizers may not be dark enough and of course they add other effects you might not want if you're just trying to shoot at f/1.2.

All these filters are just as sharp and take the same pictures, the difference is how much abuse they'll take and stay clean and stay in one piece. Since filters last a lifetime or more, there's no reason not to buy the best as it will last you for the next 50 years. Filters aren't throwaways like digital cameras which we replace every few years, like it or not. I'm still using filters I bought back in the 1970s! The Hoya HD3 stays cleaner than the others since it repels oil and dirt, and you'll be using it long after you've thrown this lens away in 50 years.

I got my RF 45mm f/1.2 from B&H. I'd also get it at Adorama, at Crutchfield or at Amazon, or get it used if you know How to Win at eBay, or get it used at KEH.

This 100% all-content, junk-free website's biggest source of support is when you use those or any of these links to my personally approved sources I've used myself for way over 100 combined years when you get anything, regardless of the country in which you live. Canon does not seal its boxes in any way, so never buy at retail or any other source not on my personally approved list since you'll have no way of knowing if you're missing accessories, getting a defective, damaged, returned, gray-market, store demo or used lens — and all of my personally approved sources allow for 100% cash-back returns for at least 30 days if you don't love your new lens. I've used many of these stores since the 1970s because I can try it in my own hands and return it if I don't love it, and because they ship from secure remote warehouses where no one gets to touch your new lens before you do. Buy only from the approved sources I've used myself for decades for the best prices, service, return policies and selection.

Thanks for helping me help you!

Ken.

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