Canon RF 1200mm F8 L IS USM Lens Review

The simultaneous announcement of the Canon RF 800mm F5.6 L IS USM Lens and Canon RF 1200mm F8 L IS USM Lens left the majority of Canon photographers wondering what Canon was thinking. Why were these two extreme lenses introduced in front of many missing mirrorless lenses? For example, RF 24mm f/1.4 and RF 35mm f/1.4 lenses remain unavailable.

Then we learned that the two new lenses shared the major design components with existing RF lenses. Specifically, the RF 400mm F2.8 L IS and the RF 600mm F4 L IS USM Lenses were used for the front of the new lenses.

"Inheriting the optical system of the "RF 600mm F4 L IS USM" that realizes weight reduction and image quality at a high level, the optimum magnifying optical system is placed at the rear of the lens..." [Canon Japan, translated]

"Optimized magnification optics increase the focal length while retaining nearly the same light weight, portability and high levels of image quality achieved in the RF600mm F4 L IS USM lens." [Canon USA]

When Canon introduced the RF 400mm F2.8 L IS USM Lens and the RF 600mm F4 L IS USM Lens, the primary change from the EF predecessor lenses was the integrated RF mount, along with a new wiring system. Introduction of the RF 800mm F5.6 L IS USM Lens and RF 1200mm F8 L IS USM Lens seemed a familiar scenario, this time with a 2x extender integrated into the back of the referenced RF 400 and RF 600 designs.

Is this the Canon RF 2x Extender? Looking at the specifications leads one to consider this possibility. The new lenses weighing slightly less and having the same number of elements and groups adds to this theory.

Model	Weight (lbs/)		Dimensions w/o Hood ("/)		Elements/Groups
Canon RF 400mm F2.8 L IS USM Lens	6.37	(2890)	6.4 x 14.4	(163.0 x 367.0)	17/13
Canon RF 400mm F2.8 L IS USM Lens + 2x	7.12	(3230)	6.4 x 15.9	(163.0 x 406.2)	26/18
Canon RF 800mm F5.6 L IS USM Lens	6.93	(3140)	6.4 x 17.0	(163.0 x 432.0)	26/18
Canon RF 800mm F5.6 L IS USM Lens + 1.4x	7.42	(3365)	6.4 x 17.8	(163.0 x 452.3)	33/22
Canon RF 600mm F4 L IS USM Lens	6.81	(3090)	6.6 x 18.6	(168.0 x 472.0)	17/13
Canon RF 600mm F4 L IS USM Lens + 2x	7.56	(3430)	6.6 x 20.1	(168.0 x 511.2)	26/18
Canon RF 1200mm F8 L IS USM Lens	7.37	(3340)	6.6 x 21.1	(168.0 x 537.0)	26/18

However, moving to the lens design diagram comparison clears up this misconception. While the new lenses feature a set of optics that double the focal length, the optics are new and optimized, including a UD (Ultra-low Dispersion) element, and shared between the two new lenses.

Note that the first and second sets of comparison images below are not sized to the same scale.

Load Comparison Images

The drop-in filter, part of the optical design, is moved behind the RF 800 and RF 1200's new integrated magnification optics. Also note that the new lenses are modestly longer than their counterparts with the RF 2x mounted.

That the based-on RF 400 and RF 600 optical designs are similar, relatively new, extremely high performing, and ultra-lightweight should be recognized.

What level of image quality should we expect from the RF 800 and RF 1200? We are accustomed to Canon's big white lenses delivering outstanding optical performance at their widest apertures, and still decent performance with extenders mounted, minimally so with the 1.4x. However, the optical designs for these lenses incorporate a 2x extender, and that design element reduces the image quality expectation.

Here are the MTF charts in a comparison format, clarifying the optical expectations.

Load Comparison Images

The higher the lines on the chart, the better the lens is performing from an optical perspective. Black lines represent contrast, while blue lines represent resolution. Solid lines represent sagittal performance, while dashed lines show meridional performance.

The bottom line is that the RF 1200 does not provide sharpness (contrast and resolution) close to the RF 600 without extenders, but it is slightly sharper than the RF 600 and RF 2x combination. The same is true for the RF 1200 vs. RF 600, with the chart showing the RF 1200 trailing the RF 800 slightly in optical performance.

The price tags on the RF 800 and RF 1200 lenses are extremely high, the highest prices ever for regular-production Canon autofocus lenses. Few will justify the above-illustrated small optical improvement for the additional $5,000.00 and $7,000.00 expenditure over the based-on lens, and Canon understands that these are low-volume lenses.

While the RF 800 F5.6 and RF 1200 F8 have a slight image quality advantage at their native focal lengths, the primary advantage of these lenses appears to be compatibility with RF 1.4x and 2x extenders that take the focal lengths to crazy-narrow angles of view. The RF 800 F5.6 extends to 1120mm f/8 and 1600mm f/11. The RF 1200mm F8 extends to 1680 f/11 and 2400mm f/16.

However, just OK optical performance magnified by an extender does not end well. In addition, f/11 image quality begins to be impacted by the softening effects of diffraction on higher resolution cameras, and f/16 will show noticeable diffraction impact even on lower resolution cameras.

Load Comparison Images

These charts do not exude optimism in regard to the expected with-extender image quality.

Back to the "Why this lens?" question. Canon already has a broad range of EF lenses that perform superbly on the EOS R-series mirrorless cameras using the Canon Mount Adapter EF-EOS R. While there is an EF 800mm f/5.6 in the line-up, that lens is showing its age (and it is heavy). There are no other 1200mm autofocus lenses available — unless you can find the long-discontinued Canon EF 1200mm f/5.6L USM Lens. Expect to add a digit to the price tag if you can find that one.

The low friction design and manufacturing efficiencies of shared components undoubtedly influenced the decision to introduce these specific models.

What is the RF 1200mm F8 L lens going to be used for? Outdoor sports, wildlife, and news photojournalism is that answer. During a conversation, Canon shared that the latest cameras' capabilities are making outstanding bird images considerably easier to capture, generating "off the charts" demand for bird photography lenses. These lenses target that need.

So, who is going to buy the RF 800 and RF 120? If you do not need a focal length shorter than 800mm or 1200mm and have the financial resources to afford the longer lens, it makes sense to get the longer lens. That said, primarily institutions, professionals at the top of their game, and serious, well-funded amateurs will own these models.

Focal Length

Back to Top

The primary reason to buy the RF 1200 is the 1200mm super-telephoto focal length. As of review time, the 1200mm focal length is differentiating, otherwise achievable only with extender combinations.

When you need to frame a subject tightly and can't get closer due to:

• Physical barriers (streams, cliffs, etc.)
• Legislated barriers (lines on a field, property boundaries, etc.)
• A subject that does not tolerate closer photographers (skittish birds, for example)
• Safety reasons (dangerous wildlife, high-speed vehicles, etc.)
• Stealth requirements (law enforcement mission, for example)
• Becoming a viewing obstruction (such as getting in front of spectators at a speaking event at a large venue)
• Laziness (sometimes relaxing is a joy of photography)

Then, you might need a 1200mm lens.

If you simply don't want to get closer, including for comfort reasons or to avoid impacting wildlife behavior, a 1200mm lens might be just right. Sit in the comfort of your car or house, avoid crossing a creek, stay back from the surf, stay out of view, etc.

When you want to capture a compressed look from a distant perspective, you might want a 1200mm lens. When you want to create an extremely strong background blur, isolating a subject from even a busy and otherwise-distracting background, a 1200mm lens might be what you need.

A 1200mm lens is primarily useful for a small subject niche, primarily wildlife, sports, and photojournalism.

This lens is for the birds.

Small wildlife, including birds, is an especially attractive subject for the 1200mm focal length.

Watch for this lens in use at events, including the Olympics, Super Bowl, World Cup, NASCAR races, and many other major sporting events. When photographers covering events are not permitted close access to their subjects, including concerts, speaking events, etc., this focal length will provide the reach needed (primarily outdoors due to the F8 max aperture opening).

Finding a subject in the narrow-angle of view provided by the 1200mm focal length can be challenging, and the 1920mm equivalent angle of view will require great skill to track a moving subject within. Moving back can be an answer, but obstacles can enter the sight path, and a longer distance permits heat waves to become a more significant issue.

While on the heat waves topic, just because you have a quality 1200mm lens doesn't mean you can create sharp images with it, even when using the fastest shutter speeds and the best techniques. When present, heat shimmer/haze/waves create optical distortion that will diminish the quality of mid- and long-distance photos, a problem I frequently encounter at half this focal length.

The sun and moon are great subjects for the 1200mm focal length. On that note, I'll borrow a focal length comparison example from the Meade Glass White Light Solar Filter Review (note that a 1200mm lens pointed at the sun without a proper filter will destroy itself and the camera in seconds).

Load Comparison Images

Here is a focal length comparison created with the RF 1200mm lens and the RF extenders.

Load Comparison Images

That is the Hunter's Moon in case you were wondering.

APS-C sensor format cameras utilize a smaller portion of the image circle, and that means a scene is framed more tightly. 1.6x is the angle of view multiplier for Canon cameras, and the APS-C angle of view, equivalent to a 1920mm full-frame angle of view, is extremely narrow. The APS-C angle of view diminishes the scenarios this lens is ideally suited for, but it is awesome for bird photography.

Max Aperture

Back to Top

The Canon RF 1200mm F8 L IS USM Lens has the longest focal length available in a lens with an f/8 max aperture. The resulting size and weight of the latest optical design at 1200mm and f/8 is relatively small and light, about as much as most photographers want to use. Canon could likely improve upon the size and weight of the last-offered 1200mm f/5.6 option, but such a lens would still be immense and heavy.

While f/8 is a narrow max aperture, aperture is measured as a ratio of lens opening to focal length. At 1200mm, an f/8 aperture is huge, and this big opening is the primary reason for the large size, heavy weight (relative to lenses in general), and high cost of this lens. That aperture is also the key to this lens's usefulness.

This lens will match or surpass the capability of all other lenses when you want to isolate the subject from even a busy, distracting background.

When you want to isolate the subject from even a busy, distracting background, this lens will match or surpass all other lenses. At f/8, the 1200mm focal length creates a shallow depth of field that combines with the strong 1200mm super-telephoto magnification to deliver the strongest background blurs available in any lens (at equivalent focus distances or subject framing, equal to 600mm f/4). Most of the common uses for this lens do not permit manipulation of the background, and the backgrounds found in many of the venues this lens will be used in tend to be busy and distracting. Use this lens to blur the distractions away, turning advertisement banners, fans, and their clothing, apparatus, gear, seating, brush, etc., into blurs of color, making the subject stand out, popping from the frame.

The above example is just in case you didn't already envision the maximum blur this lens can create.

It is likely many of these lenses will never be used with an aperture other than f/8, though narrower apertures are available.

While the magnification from a 1200mm focal length makes capturing sharp images challenging, the f/8 aperture increases the challenge for great image quality. Especially for a focal length typically used to capture subjects in motion, relatively fast f/8 shutter speeds usually require high ISO settings, and high ISO settings bring noise.

The above woodpecker image was captured at 1/200 and processed to about ISO 2500. Here are some additional exposure examples:

The cardinal, sitting in direct late-day sunlight, was exposed at 1/250 and processed to ISO 6400. I know, the legs are cut off, but what a nice pose otherwise.

The squirrel in direct sunlight was captured at 1/125 and ISO 800, and the chipmunk image below used 1/80 and ISO 800.

As you likely recognized, the shutter speeds just listed are not adequately fast for good keeper rates. As a result, a high percentage of the images from these slow-shutter sessions were motion-blurred.

Thousands of images have taught me that this lens requires good shooting technique, along with fast shutter speeds that mandate high ISO settings.

Image Stabilization

Back to Top

The longer the focal length, the larger subject details (captured at the same distance) are rendered, and the more still the camera must be held to avoid subject details crossing imaging sensor pixels, the cause of motion blur. Image stabilization is an extremely valuable feature in any lens and especially in a telephoto lens. Capturing sharp imagery from a large 1200mm lens may require image stabilization even when mounted on a solid tripod.

Practically everything in the EF 600mm f/4L IS III lens was new, including the image stabilization system that achieved an impressive up to 5-stop CIPA rating. The RF 600mm F4 L IS Lens upped that rating slightly to 5.5 stops, with the increase directly attributed to the RF mount (note that this lens does not support coordinated IS, but IBIS is said to still provide some benefits). Based on this RF lens, the RF 1200mm F8 gets a rating that is a bit lower — 4.0 stops.

Rudy Winston, Canon USA, shares:

"Canon engineers claim no Coordinated IS with the RF800mm F5.6 L IS and 1200mm F8 L IS lenses. In-body IS has always had limits in effectiveness with progressively longer telephoto lenses – requiring more and more sensor movement to counter camera/lens shake, which obviously is effectively magnified by the longer focal lengths.

Our claim is 4.5 stops of *optical* IS with the RF800mm, and 4.0 stops of optical IS with the 1200mm. There's no word as to whether the IBIS system in cameras like the R3, R5 and R6 is totally shut down, or its effectiveness is minimized... keep in mind, however, that we claim the SAME stabilization correction with non-IBIS-equipped cameras like the EOS R, based on CIPA-compliant testing."

While the RF 1200mm lens is light for its specifications, it is still not a light lens to handhold, and the extremely narrow-angle of view increases the handholding challenge. Still, IS should make handheld shooting possible with this lens.

Three stabilization modes are provided. Mode 1 (general-purpose), Mode 2 (for panning with a subject, one axis of stabilization is provided), and Mode 3. Mode 3 is useful for tracking erratic action. In this mode, image stabilization is active and ready for use the moment the shutter releases, but actual stabilization is not in effect until that precise time. As a result, the view seen through the viewfinder is not stabilized, allowing an erratically moving subject to be tracked without fighting against image stabilization trying to stabilize the view. Mode 3 is designed to detect panning motion, and when detected, the lens will only apply stabilization at right angles to the direction of the detected movement (like Mode 2).

The latest word from Canon is that mode 1 can optimally be used for nearly all situations, including while using a tripod or monopod and while photographing action. I find mode 3 IS optimal for tripod-mounted photography, yielding a stable view for composition yet compensating for vibrations, especially those caused by wind, during the exposure.

Expect a click to be quite audible when IS starts and again when it stops but only quiet whirring and clicking while IS is active. This IS implementation is exceptionally well-behaved – the image in the viewfinder does not bounce when the system activates, and the image does not drift while IS is active. IS aids greatly in establishing ideal handheld subject framing.

Canon's super-telephoto lenses have a secondary IS mode that automatically senses a tripod in use, then attempting to eliminate shutter shock, wind vibration, and other sources of remaining movement.

While stopping camera motion-induced image blur is image stabilization's primary job, it has another significant benefit, aiding in AF precision. The camera's AF system can produce better focus precision if the image it sees is stabilized. Canon contends that this is true even with a subject in motion, and the 1200mm f/8 combination producing a potentially shallow depth of field makes AF precision especially critical.

The weight of this lens enables it to be handheld for significant periods, and the image stabilization system in this lens greatly extends its versatility in that regard.

Note: when this lens is dismounted while the camera is powered on, the IS unit may make a rattle sound when the lens is moved.

Image Quality

Back to Top

I usually start the image quality section of a super-telephoto lens review with superlatives. However, as expected and as discussed in-depth at the beginning of the review, this lens does not perform at the same level as the RF 600 L.

For the price of this lens, the sharpness performance is mediocre. However, it performs closer to the referenced worthy of the superlatives lens than expected. The RF 1200mm lens outperforms the RF 600 with an RF 2x extender, making it the best available option at 1200mm.

Selecting a one or two stops narrower aperture often provides at least minor sharpness improvement. However, with a wide-open aperture starting at f/8, diffraction is already playing a softening role at only one stop narrower, offsetting any gains realized using that technique. The f/11 test results appear the same as the f/8 results.

The corner image quality varies little from that in the center of the frame.

The resolution chart is brutal/merciless on image quality, so let's take the testing outdoors, next looking at a series of center-of-the-frame 100% resolution crop examples. These images were captured using an ultra-high resolution Canon EOS R5 with RAW files processed in Canon's Digital Photo Professional (DPP) using the Standard Picture Style with sharpness set to 1 on a 0-10 scale. Note that images from most cameras require some level of sharpening, but too-high sharpness settings are destructive to image details and hide the deficiencies of a lens.

Load Comparison Images

These results will look great if sharpened slightly.

When used on a camera that utilizes a lens's entire image circle, a lens can be expected to create peripheral shading at the widest aperture settings. Utilize a 2x extender, and only the center of the image circle, where the least vignetting shows, is utilized.

About one stop of peripheral shading shows in full frame corners, and under 1/2 stop is present in APS-C corners. Most of that shading is gone at f/11.

One-stop of shading is often used as the visibility number, though subject details provide a widely varying amount of vignetting discernibility. Vignetting is correctable during post-processing, with increased noise in the brightened areas being the penalty, or it can be embraced, using the effect to draw the viewer's eye to the center of the frame. Study the pattern shown in our vignetting test tool to determine how your images will be affected.

Lateral (or transverse) CA (Chromatic Aberration) refers to the unequal magnification of all colors in the spectrum. Lateral CA shows as color fringing along lines of strong contrast running tangential (meridional, right angles to radii), with the mid and especially the periphery of the image circle showing the most significant amount as this is where the most significant difference in the magnification of wavelengths typically exists.

This lens shows negligible lateral CA in the corners and an inconsequential amount of geometric distortion.

Multiplying the RF 600's good bokeh by 2x does not reduce the quality.

Overall, the Canon RF 1200mm F8 L IS USM Lens delivers good image quality. The image quality is not as good as Canon's RF 400 and RF 600 L lenses, but when I use the settings and technique required to get sharp 1200mm images, the results look good. Here is one more f/8 sample crop. This image was processed the same as the earlier crops with the exception of the ISO 1250 noise being reduced by a 4.7 setting for luminance and chrominance.

Increase the sharpness amount by 1, and this is the result:

Focusing

Back to Top

Critical for the success of a lens creating a shallow depth of field and used primarily to photograph subjects in motion is its AF performance. Canon's super-telephoto lenses have long delivered the best-available autofocus performance, and this lens is expected to continue that trend.

However, extenders have an impact on AF speed, and the RF 1200 has an integrated 2x extender. Additionally, the relatively narrow maximum f/8 aperture further impacts AF performance. Still, the RF 1200 AF system performs well, quickly focusing on subjects until low light conditions are encountered.

Mounting an external extender behind a lens further reduces AF speed. However, the difference is minor, and this lens focuses quickly even with a 2x behind it. Expect the camera's AF area to be reduced with the 2x, and focus hunting becomes more common with the increased magnification and decreased max aperture.

Based on the RF 600, the RF 1200's AF system incorporates that lens's AF advantages. "Mechanically-related AF improvements include reduced drive load, thanks to glass materials in the focus lens group that are nearly one-fifth the previous weight." [Canon] Also included is the latest microprocessor for improved calculation speed.

In addition to being reasonably fast and accurate, this lens's internal AF system is quiet. Some internal shuffling, along with quiet clicks, is heard by an ear near the lens.

This super-telephoto lens includes a Focus Preset feature. Set the Focus Preset to a specific distance. When your shooting needs require that particular distance, turn the white spring-loaded playback ring located in front of the focus ring, and the lens automatically adjusts to the preset distance. New with the EF 600mm III lens was a direction-sensitive feature that permits a different distance to be set for each rotation direction. The Focus Preset switch settings include OFF, ON, and an ON with audible focus confirmation. Use this feature to quickly adjust focus to a known distance or to an approximate distance where fine-tuning can quickly attain proper focus.

A 3-position focus limiter switch allows focusing distances to be limited to a subset of this lens's focus distance range. In addition to the full range, restricted limits of 14.1-98.4' (4.3-30m) and 98.4' (30.0m) - ∞ are selectable for improved focus lock times and reduced focus hunting when photographing subjects remaining within these ranges.

Four autofocus stop buttons in the black ring near the objective lens allow autofocus to be temporarily stopped. I use Servo (continuous) focusing mode for shooting sports but sometimes shoot focus-and-recompose images such as portraits during the event. The autofocus stop feature makes it easy to obtain focus lock, turn off autofocus, and recompose with framing that places the active focus point(s) off of the subject, including in the periphery of the frame. Another excellent use for this feature is when an image has been captured with suboptimal framing. Simply press a focus stop button and then capture enough images to be stitched together during post-processing. Of course, switching the lens to manual focus mode has the same effect.

New on the 2010-announced super-telephoto lenses was a third focusing mode. In addition to AF and MF, a "PF" or Power Focusing mode was included, and this mode has returned with the RF and series III lenses. When first introducing this feature, Canon USA said the feature helped "...moviemakers achieve smoother and more appealing focus shifts when filming."

Turn the focus preset playback ring (very) slightly to get low-speed electronically-driven AF, and turn it to a greater degree to obtain a higher rate with the direction of ring rotation determining the direction of focus distance change. The feature works nicely, but you will need a solid tripod setup and a steady hand not to induce movement while turning the ring. The power focusing is extremely quiet. Note that AF does not work in PF mode, though manual focusing is available in this mode.

Those interested in manually focusing this lens have not been forgotten, and this lens's focus ring lens will provide a superb manual focus experience. Instead of a conventional mechanically-linked manual focus drive, Canon implemented electronic manual focusing starting with the EF 600mm III lens. This decision simplified the overall design, saving weight and increasing expected reliability — and seemingly preparing for the R-series technology.

The RF 1200mm F8 L IS lens's manual focus ring is ideally located, is large, has a sharply-ribbed rubber surface with a great feel and ideal rotational resistance, and will be smooth with no play. With an ear against the lens, a series of tightly-spaced click sounds will be heard while manually focusing.

A feature commonly implemented on electronic focusing lenses is variable speed drive rate dependent on the focus ring rotational speed. Unfortunately, this feature is often not optimally implemented, and fortunately, Canon has a better option for this lens. Via a switch, this lens offers three linear drive speeds. Mode 1 adjusts the focus relatively quickly, and precise focusing is challenging in this mode. Mode 2 and 3 become respectively slower, enabling fine control over the focus distance. You don't want to use mode 3 setting to chase sports action, but this mode allows for precise manual focusing.

FTM (Full Time Manual) focusing is supported in AF mode while in One Shot Drive Mode, but the shutter release must be half-pressed for the focus ring to be enabled. I often manually adjust the focus distance to track action while I'm not actively shooting, such as to watch sports action at the other end of the field or to pre-focus on where I expect the action to occur next. Note that FTM does not work if electronic manual focusing is disabled in the camera's menu (if this option is present). The lens's switch must be in the "MF" position and the camera meter must be on and awake for conventional manual focusing to be available.

The RF 1200 is well-suited for AF during video recording. The smooth focusing will make focus distance transitions easy on the viewer's eyes.

Canon super-telephoto lenses generally do not have the shortest minimum focusing distances among lenses in general. The latest Canon RF and EF 600mm F4 L IS Lenses improved upon previous versions in this regard. Maintaining a similar minimum focus distance with twice the focal length gives the RF 1200mm lens a significant among all lenses 0.29x maximum magnification.

Following is a comparison table showing the recent and current Canon super-telephoto line-up as of review time.

Model	Min Focus Distance "(mm)		Max Magnification
Canon RF 100-500mm F4.5-7.1 L IS USM Lens	35.4	(900)	0.33x
Canon RF 200-800mm F6.3-9 IS USM Lens	31.5	(800)	0.25x
Canon RF 100-500mm F4.5-7.1 L IS USM Lens	35.4	(900)	0.33x
Canon RF 400mm F2.8 L IS USM Lens	98.4	(2500)	0.17x
Canon RF 600mm F4 L IS USM Lens	165.4	(4200)	0.17x
Canon RF 600mm F11 IS STM Lens	177.2	(4500)	0.14x
Canon RF 800mm F5.6 L IS USM Lens	102.4	(2600)	0.34x
Canon EF 800mm f/5.6L IS USM Lens	236.2	(6000)	0.14x
Canon RF 800mm F11 IS STM Lens	236.2	(6000)	0.14x
Canon RF 1200mm F8 L IS USM Lens	169.3	(4300)	0.29x
Sony FE 600mm f/4 GM OSS Lens	177.6	(4510)	0.14x

A subject measuring approximately 4.6" x 3.1" (117 x 78mm) will fill the RF 1200mm frame at the minimum focus distance.

Load Comparison Images

Extenders / Teleconverters

Back to Top

As mentioned at the beginning of this review, the Canon RF 1200mm F8 L IS USM Lens is compatible with the Canon RF 1.4x Extender and the Canon RF 2x Extender.

With the 1.4x behind it, this lens becomes a 1680mm f/11 lens. With the 2x mounted, it becomes a tremendously long 2400mm f/16 lens.

Weather sealing and image stabilization are included. In addition, the lens's native minimum focusing distance is retained with extenders in use, and that means the maximum magnification value is multiplied by the extender's multiplier, a significant improvement.

With the RF 1.4x behind the RF 1200 L, image sharpness is decreased moderately. With the effects of diffraction becoming more apparent, stopping down 1 stop to f/16 shows no improvement in sharpness. The RF 1.4x adds a tiny amount of barrel distortion but does not affect lateral CA.

As always, the image sharpness hit with the 2x is stronger than with the 1.4x, and 2400mm f/16 results are rather soft. The results at f/22, with the softening effects of diffraction becoming significant, are not good. The 2x increases lateral CA and slightly increases barrel distortion.

Let's view a comparison created in the studio. These images were captured with a Canon EOS R5. The RAW files were processed in Canon's Digital Photo Professional (DPP) using the Standard Picture Style with sharpness set to 1 on a 0-10 scale. 100% crops are shown. The camera stand was stationary for the capture of these test images — the with-entender results show enlarged details.

Load Comparison Images

While the 2x results are noticeably softer than the others, I find the 1.4x results surprisingly good.

Mounting an external extender behind a lens further reduces AF speed, but the with-extender autofocus performance of the Canon EOS R-series cameras is remarkably good. In this case, the difference is minor, and the RF 1200mm lens focuses quickly, even with a 2x behind it. Expect the camera's AF area to be reduced with the 2x in place, and focus hunting becomes more common with the increased magnification and decreased max aperture.

Build Quality & Features

Back to Top

Canon's big white super-telephoto lenses are among the most elite DSLR lenses available and represent the Canon L Series's best. Professionals expect these lenses to deliver the ultimate performance in the most adverse environments. Despite the significant weight loss, the overall durability of the RF and EF version III 600mm lenses was increased over the already-impressive version II model, and the RF 1200 is based on these lenses.

Improvements in manufacturing processes get some of the credit for the light weight strength, and fascinating is the use of a new carbon-reinforced magnesium alloy. "The high level of fluidity in this material enables injection molding (thixomolding) for a thin walled formation. For example, with the first group lens barrel on the 400mm model, we were able to achieve a barrel thickness of 0.8mm via injection molding, for a base that is 20% thinner than previous models, maintaining sufficient strength and lightness. The carbon-reinforced magnesium alloy is also used for the tripod base plate and the exterior of the barrel." [Canon]

As lens size increases, the difficulty of maintaining precision increases, and attention to detail has been shown in this lens design.

Load Comparison Images

As discussed, the RF 1200 F8 L IS Lens utilizes the RF 600mm F4 L IS Lens design for its front, with an extended mount section to the rear.

This lens's switches are mostly recessed, with just enough raised surface to be usable with gloves on. Note that the IS ON/OFF switch is raised in the center vs. both sides for tactile differentiation.

As already mentioned, the focus ring feels great, and the shape of this ring aids in the quality experience. The focus recall ring is easy to locate tactilely, and a diamond pattern black ring provides a grip for handling.

Notably missing on this RF lens (and its design-sharing predecessor) is a control ring.

The color of this lens deserves attention. Heat gain, especially uneven heat gain, can cause problems for a lens's optical performance, and big lenses have a lot of surface area to catch sunlight. Canon has chosen white paint to avoid as much heat gain as possible, and the new paint formulation on the III better shields the lens from heat than the previous paint did. "Infrared reflective pigments with high reflectance and titanium oxide lens barrel coating with silica provide excellent UV weather resistance and heat reduction." [Canon] But, that is just the beginning of the heat-avoidance efforts designed into the RF and version III lenses.

A newly-developed heat shield coating reduces uneven heating, and a two-layer barrel structure design also helps mitigate thermal transfer effects into the lens elements. In addition, reducing the weight of the lens naturally reduces its overall thermal capacity.

This lens features excellent weather resistance (the RF 600m F4 L IS Lens sealing is illustrated above). Many outdoor events are held regardless of the weather, and the photographers required to cover them are forced to deal with the weather. While I recommend a rain cover when wet weather is expected, the unexpected that can be a bigger problem. I've used Canon weather-sealed super-telephoto lenses in rather heavy rain with no ill effects. In addition to being sealed from moisture, dust is another hazard this lens keeps out.

The front and rear lens elements are fluorine-coated for easier cleaning and to prevent dust and drips from adhering in the first place.

You will immediately recognize the ultra-high-quality construction when you pick up this lens.

The RF 1200 can easily be handheld for reasonable periods, but a 7.4 lb (3340g) lens is not light for use in this manner.

The size of this lens garners attention. You look like you belong in some venues, and you will stand out in others. You'll get over the latter. Regarding the former, I find a lens such as this one gains me entrance to locations in venues that I would otherwise have been restricted from.

Here is a table of comparable Canon telephoto lenses with the size and weight specifications included.

Model	Weight (lbs/)		Dimensions w/o Hood ("/)		Filter	Year
Canon RF 100-500mm F4.5-7.1 L IS USM Lens	3.0	(1365)	3.7 x 8.2	(93.8 x 207.6)	77	2020
Canon RF 200-800mm F6.3-9 IS USM Lens	4.5	(2050)	4 x 12.4	(102.3 x 314.1)	95	2023
Canon RF 400mm F2.8 L IS USM Lens	6.4	(2890)	6.4 x 14.4	(163.0 x 367.0)	DI 52	2021
Canon RF 600mm F4 L IS USM Lens	6.8	(3090)	6.6 x 18.6	(168.0 x 472.0)	DI 52	2021
Canon RF 600mm F11 IS STM Lens	2.1	(930)	3.7 x 10.6	(93.0 x 269.5)	82	2020
Canon RF 800mm F5.6 L IS USM Lens	6.9	(3140)	6.4 x 17.0	(163.0 x 432.0)	DI 52	2022
Canon EF 800mm f/5.6L IS USM Lens	9.9	(4470)	6.4 x 18.1	(163.0 x 461.0)	DI 52	2008
Canon RF 800mm F11 IS STM Lens	2.8	(1260)	4.0 x 14.2	(101.6 x 361.8)	95	2020
Canon RF 1200mm F8 L IS USM Lens	7.4	(3340)	6.6 x 21.1	(168.0 x 537.0)	DI 52	2022
Canon EF 1200mm f/5.6L USM Lens	36.4	(16500)	9.0 x 32.9	(228.0 x 836.0)	DI 48	1993
Sony FE 600mm f/4 GM OSS Lens	6.7	(3040)	6.4 x 17.7	(163.6 x 449.0)	DI 40.5	2019

For many more comparisons, review the complete Canon RF 1200mm F8 L IS USM Lens Specifications using the site's lens specifications tool.

While the RF 1200 is relatively light and handholdable, I will primarily use this lens on a support for both comfort and stability reasons. Still, lighter weight makes it easy to lift the monopod off the ground to follow fast action handheld. Use the monopod to rest the setup between breaks in the action.

Here is a visual comparison:

Positioned above from left to right are the following lenses:

Canon RF 400mm F2.8 L IS USM Lens
Canon RF 800mm F5.6 L IS USM Lens
Canon RF 600mm F4 L IS USM Lens
Canon RF 1200mm F8 L IS USM Lens

The same lenses are shown below with their hoods in place.

Use the site's product image comparison tool to visually compare the Canon RF 1200mm F8 L IS USM Lens to other lenses.

The RF 1200 F8 L IS utilizes the same 52mm drop-in filters as its 600mm predecessor and most of Canon's super-telephoto lenses. This lens's slot includes a drop-in filter holder that accepts 52mm threaded filters. A slim Canon Protect 52mm threaded filter comes installed. Note that the filter is part of the optical design of Canon's big lenses, effectively the rear element in the optical path. It also helpful for catching dust before it drops deep inside the lens.

The Canon Drop-In Circular Polarizing Filter PL-C 52 (WIII) may sometimes be found helpful. This filter has had several revisions solely for color changes, keeping up with the lens color changes. Subtracting light from an already narrow aperture is not so often needed or appreciated, but some may find neutral density filters useful for this lens, primarily for video recording in bright light.

The tripod foot has two differently-sized threaded inserts — 1/4" and 3/8". A Wimberley P50 Lens Plate permits quick attachment to Arca-Swiss compatible monopod and tripod head clamps. Mounting with two screws is important to prevent the plate from twisting, but note that most lens plates will require a 3/8"-16 to 1/4"-20 Reducer Bushing in the larger threaded insert. These are inexpensive, and it seems Canon could easily have included one in the box. Much better would have been to machine the needed Arca-Swiss dovetail grooves into the foot, as some other lens manufacturers do.

Replacing the Canon tripod foot with a Wimberley (used in some of the product images in this review) or Really Right Stuff Tripod Foot is popular and my preference.

Lens plates and replacement feet better permit ideal balancing on a tripod or monopod, especially helpful due to the balance point of the lens with a gripped camera mounted is slightly back from the rear threaded insert.

This tripod collar is exceptionally smooth and provides light click-stops at 90°-degree rotations. While the click-stops cause a slight bump during rotation (such as when panning with a subject as a monopod tilts), I prefer to have the click-stops assisting me with finding center, aiding significantly in maintaining a level camera.

This super-telephoto lens's light weight reduces the demands of its support, but the exceptionally long focal length increases the vibration-dampening requirement. As I've mentioned, this lens can be handheld for a time, but you will appreciate having support under the lens for longer periods (and for stabilizing the view). Avoiding future shoulder issues may not seem important today, but I assure you that you will one day appreciate having taken good care of your body in your youth. Keep your elbows in and shoulders at rest.

For tripod mounting, I recommend using a strong ball head (such as the Really Right Stuff BH-55) with this lens. Much better (safer, easier) is to use a lens of this size on a gimbal-style head such as the Wimberley WH-200-S Sidemount Head.

Two tripod collar feet were included with the EF 600mm f/4 version II lens, with one being a small foot designed for monopods. I never used the small one, and apparently, many others left their small foot in the box. The smaller monopod base plate is reportedly again available for the RF lenses, but it is now an optional accessory.

As first seen on the 600 IS II, the RF 1200 F8 has a Kensington-type wire security lock under the tripod collar lock knob cap.

Load Comparison Images

Sharing the same front design, the RF 1200mm F8 and RF 600mm F4 unsurprisingly share the same lens hood model. The included ET-160 (WIII) lens hood is relatively rigid, rather light (10.6 oz / 300g), and huge, offering the lens element excellent protection from bright light, impact, and the elements. While this hood is quite rugged, it bears protection as a replacement will cost as much as a nice lens.

The big lens hood is sometimes an issue from a space standpoint, including packing space and space on the sidelines or at other events. There is the optional Canon ET-160B Short Lens Hood for those circumstances. The price tag is substantial for this version also.

The E-185C lens cap features a padded, rigid interior that protects the front lens element and a wrap-around nylon cover.

The included padded lens strap can be attached to the tripod ring, an attachment point that permits the camera to be rotated without the neck strap twisting around one's neck.

The Canon LS1200 Soft Lens Case, a sling-style (single strap) shoulder case similar to the LS600 (shown above), is included in the box.

This nylon case looks great, is relatively compact and lightweight, well-padded, easy to use with smooth-functioning zippers and large pulls, and has a round molded-plastic bottom that keeps it upright on a flat surface. A thin zippered pocket and a pair of strap attachment points are provided on both sides of the case. The shoulder strap is padded and strong, and breathable padding is provided on the strap's case side, adding to the shoulder-carrying comfort. The convenient hand strap on top is also strong, with breathable padding ensuring that grip is not lost. Four hook-and-loop-adjustable pads are provided for interior use.

This case is nicely sized to hold its intended cargo.

The LS600 is shown above.

Price, Value, Compatibility

Back to Top

A low-volume niche lens with extremely high production costs results in an extremely high price tag. Only a select few photographers will find the cost-value proposition balanced favorably for a purchase.

As an "RF" lens, the Canon RF 1200mm F8 L IS USM Lens is compatible with all Canon EOS R-series cameras. Canon USA provides a 1-year limited warranty.

The reviewed Canon RF 1200mm F8 L IS USM Lens was online-retail sourced.

Alternatives

Back to Top

The primary alternative to the Canon RF 1200mm F8 L IS USM Lens is the Canon RF 600mm F4 L IS USM Lens, with the Canon RF 2x Extender creating an equivalent 1200mm f/8 lens from this model. The 600mm lens provides 600mm f/4 and 840mm f/5.6 options, but it does not have an answer to the 1200mm + extender 1680mm f/11 and 2400mm f/16 capabilities.

As expected, the bare RF 600mm F4 L Lens is sharper than the RF 1200. However, the RF 1200 is sharper than the RF 600 + 2x, and the difference is bigger than expected. Obvious is that the internal 2x outperforms the external 2x.

The Canon RF 1200mm F8 L IS USM Lens vs. Canon RF 600mm F4 L IS USM Lens comparison without the 2x factored in shows the RF 600 modestly lighter and shorter. However, the 2x is needed to balance this comparison, and with that optic factored in, the RF 600 tips the scales toward itself slightly, though it remains slightly shorter. Most other factors are equalized when the RF 2x is included in the comparison. The RF 600 + RF 2x is considerably less expensive than the RF 1200, and it is the optimal choice for a high percentage of photographers considering these options.

The Canon RF 800mm F5.6 L IS USM Lens was simultaneously introduced with the RF 1200. Adding the Canon RF 1.4x Extender to this lens yields an 1120mm F8 lens. While not identical, the 1120mm and 1200mm focal lengths are close enough for the difference to matter little in comparison. The 800mm lens offers 800mm f/5.6, and the RF 1200 goes longer with the 2x mounted, 2400mm vs. 1600mm.

As illustrated in the MTF comparison at the beginning of this review and proven in the image quality comparison, the RF 1200mm image quality is better than the RF 800mm + 1.4x image quality. Further, our tests show that the RF 1200mm image quality is better than the RF 800mm image quality.

The Canon RF 1200mm F8 L IS USM Lens vs. Canon RF 800mm F5.6 L IS USM Lens comparison without the 1.4x factored in shows the RF 800 modestly lighter and smaller. However, the 7.9 oz (225g) 1.4x is needed to balance this comparison, and with that optic factored in, the RF 800 becomes slightly heavier but still modestly shorter. With a shorter minimum focus distance, the RF 800 has a higher maximum magnification (0.34x vs. 0.29x), and the 1.4x extends that difference (0.48x vs. 0.29x). The RF 800 + RF 1.4x is less expensive than the RF 1200, though both options are high-priced.

The Canon RF 600mm F4 L IS USM Lens and Sony FE 600mm F4 GM OSS Lens are similarly sharp at f4. However, the Sony lens performs better with extenders/teleconverters.

For about the price of the RF 1200 L, the Sony 600 F4, a 2x, and a pro body (Sony Alpha 1) can be purchased. Thus, the Canon vs. Sony comparison seems relevant.

The Canon RF 1200 vs. Sony FE 600 + 2x image quality comparison shows these two options performing similarly.

The Canon RF 1200mm F8 L IS USM Lens vs. Canon RF 600mm F4 L IS USM Lens comparison without the 2x factored in shows the Sony 600 modestly lighter and shorter. However, the 2x is needed to balance this comparison, and with that optic factored in, the Sony 600 tips the scales toward itself slightly, though it remains shorter. Most other factors are equalized when the RF 2x is included in the comparison. The Sony 600 and 2x combination is considerably less expensive than the RF 1200, and it is the optimal choice for a high percentage of photographers considering these options. The 600mm lens provides 600mm f/4 and 840mm f/5.6 options, but it does not have an answer to the 1200mm + extender 1680mm f/11 and 2400mm f/16 capabilities.

Use the site's tools to create additional comparisons.

Summary

Back to Top

As shared, the Canon RF 1200mm F8 L IS USM Lens is a niche lens, optimal for those requiring the 1200mm focal length more than occasionally or needing a focal length longer than 1200mm. If the niches targeted by this lens are important to you, primarily wildlife, sports, and photojournalism, there is no better 1200mm or longer option for it.

Due to the extreme cost of the RF 1200mm lens, the opportunity for unique imagery is readily available to those owning it.

This has been a fun lens to have available.