Canon EOS R5

Manufacturer: Canon
Type: Mirrorless camera (full-frame)
Year introduced: 2020
Sensor: 45MP full-frame CMOS
Price: $3,899 (body only at launch)
Mount: Canon RF
Key feature: First camera with internal 8K RAW video recording

Overview

The Canon EOS R5 was Canon’s flagship full-frame mirrorless camera and one of the most significant camera launches in the history of underwater photography. First teased in early 2020, with video specifications confirmed at a live press conference on April 20, 2020 (^[1]), and formally announced on July 9, 2020 alongside the Canon EOS R6, the RF 85mm f/2 Macro IS STM lens, and RF 1.4x/2x teleconverters (^[2]).

At 45 megapixels with internal 8K/30p RAW video recording — the first camera to offer this capability — 4K/120p, and 5-axis in-body image stabilization (IBIS), the R5 was immediately recognized as a landmark product. Canon described the R5 and R6 as “the company’s most advanced full-frame mirrorless cameras ever” and “the result of many years of collecting and listening to feedback from Canon users” (^[3]).

For underwater photographers, the R5’s combination of resolution, video capability, advanced autofocus, and Canon’s established lens ecosystem made it the most eagerly anticipated mirrorless camera since the Sony a7R II. Its announcement triggered what became the largest simultaneous housing development race of the mirrorless era, with every major housing manufacturer announcing support within 16 months.

Key Specifications

• Sensor: 45MP full-frame CMOS, new design (^[4])
• Processor: DIGIC X
• Video: 8K/30p RAW internal (uncropped), 8K/30p 4:2:2 10-bit Canon Log/HDR PQ, 4K/120p 4:2:2 10-bit, external 4K/60p via HDMI (^[5])
• Image stabilization: 5-axis IBIS, up to 8 stops combined with IS-equipped RF lenses (^[6])
• Autofocus: Dual Pixel CMOS AF II with EOS iTR AF X, 1,053 AF zones, ~100% coverage; subject tracking via deep learning (human eye/face/head, animal eye/face/body for dogs, cats, birds) (^[7])
• Burst rate: 12 fps mechanical shutter, 20 fps electronic (silent) shutter
• ISO range: Native 100–51,200 (expandable to 102,400)
• EVF: 0.5-inch OLED, 5.76 million dots, 119.88 fps refresh rate
• LCD: 3.2-inch vari-angle touchscreen, 2.1 million dots
• Card slots: 1x CFexpress, 1x SD UHS-II
• Connectivity: 5GHz/2.4GHz Wi-Fi, Bluetooth
• Weather sealing: On par with Canon EOS 5D series
• Other features: 10-bit HDR photos in HEIF format, voice tagging for photos/videos
• Price: $3,899 body only; $4,999 with RF 24-105mm f/4L IS USM kit lens (^[8])
• Availability: End of July 2020

Housing Availability

The EOS R5 drove simultaneous housing development across every major manufacturer — the broadest and fastest housing race of the mirrorless era. Seven housing manufacturers announced or shipped housings within 16 months of the camera’s announcement:

Seacam Silver EOS R5

Seacam was the first to announce, posting on Facebook on July 16, 2020 — just one week after the camera’s announcement — that it was developing a Silver housing for the R5 (^[9]). On January 16, 2021, Seacam released images and full details, showing compatibility with their port system, three standard ports for vacuum/remote/strobe triggering, and a specific HDMI 2.0 bulkhead. Owner Harald Hordosch was photographed with the finished housing (^[10]). Seacam also announced a companion housing for the Atomos Ninja V recorder/monitor, designed to work with the R5 for external recording.

Ikelite 200DL

Ikelite announced their 200DL housing on August 20, 2020, at $1,695 — the most affordable option. It featured Ikelite’s Dry Lock port system, integrated vacuum valve, M16 accessory port, and the option of TTL or manual strobe control via electrical connection. Rated to 200 feet (60m). The housing weighed 4.7 lb without tray and handle. Ikelite specifically noted the housing was only compatible with the EOS R5 and could not accommodate the R6 (^[11]).

Nauticam NA-R5

Nauticam shipped their NA-R5 in September 2020, the first aluminum housing to reach customers. At $3,965, it used the N120 port system, providing compatibility with both RF and EF lenses (via Canon’s EF-to-RF mount adapters). The housing featured Nauticam’s “Mission Control” ergonomic design with dual thumb levers and sub-levers accessible from the handles, integrated vacuum check and leak detection system (shipped as standard), and fiber optic bulkheads for flash triggering. Dimensions were 357mm x 200mm x 161mm, weight 3.5kg in air, nearly neutral in water at -0.05kg with camera and battery. Depth rated to 100m (^[12]).

The NA-R5 also supported HDMI 2.0 output to the Nauticam Atomos Ninja V housing for external recording, using a dedicated HDMI 2.0 cable system. An additional control wheel on the left side interfaced with the control ring on Canon’s EF to EOS R Mount Adapter with Control Ring (^[13]).

A notable early user comment on the Nauticam announcement came from Tino Brandt, who observed that Canon had built a recording timer into the R5 that shortened video recording time regardless of temperature, limiting the camera’s 8K video potential underwater (^[14]).

Sea & Sea MDX-R5

Sea & Sea announced their MDX-R5 on December 15, 2020. It featured their MDX port system, compatibility with both RF and EF lenses, a 24mm bulkhead for HDMI 2.0 output, built-in leak sensor, fiber optic and electronic sync triggering, ergonomic grip handles with colored controls for visibility, luminescent stickers on controls for low-light use, and a port lock system. Constructed from corrosion-resistant machined aluminum with anodized finish. Dimensions 345mm x 173mm x 164mm, weight approximately 2,900g including grips, depth rated to 100m (^[15]).

Isotta EOS R5

Isotta shipped their signature red anodized aluminum housing in June 2021 at €2,790. It featured Isotta’s hallmarks: one-handed opening, double O-ring seals on all moving parts, ergonomic adjustable handles, a completely detachable rear, two built-in fiber optic connectors, three M16 ports and one M24 port for accessories/vacuum/HDMI, a moisture sensor with LED and audible alert, and a 120mm bayonet port mount. Depth rated to 100m (^[16]).

Inon EOS R5

Inon announced their housing on October 28, 2021, with shipping in November. Uniquely among R5 housings, it was manufactured via cast aluminum rather than machined, enabling a thinner body with complex curved designs. The housing shipped with several features as standard that were optional on competing housings: Inon’s proprietary TTL converter (calibrated specifically for underwater environments), vacuum leak sensor, handles, tray, and quick-mount brackets that allowed switching between horizontal and vertical camera orientation underwater. The TTL converter supported 12fps continuous shooting in TTL mode, operated for 100,000+ shots on two CR2032 batteries, and offered rear curtain sync support. Supported lenses included the Canon RF 35mm f/1.8 Macro, Canon EF 8-15mm f/4L Fisheye, Sigma 70mm f/2.8 DG Macro, Canon RF 85mm f/2 Macro, Canon RF 100mm f/2.8L Macro, and Canon EF 100mm f/2.8L Macro (^[17]).

Marelux

Marelux, a new housing brand introduced in December 2021 by underwater photographer Vladimir Mladenovic, launched with housings for several mirrorless cameras including the Canon EOS R5/R6. The company positioned itself as offering high quality, best-in-class ergonomics, and competitive pricing with established brands (^[18]).

TTL and Strobe Triggering

TTL strobe control was a significant topic for R5 users, as the camera introduced changes to Canon’s TTL protocol that required firmware updates from TTL converter manufacturers.

Underwater Technics TTL Converter

Underwater Technics shipped their TTL converter for the R5 in Nauticam housings (product #11052-HSS-R) in May 2021. Developed by Pavel Kolpakov, the converter featured both optical and electrical strobe triggering on a single board, HSS support (up to 1/8000s with Retra strobes), rear curtain sync, automatic on/off via camera command, and full Canon menu integration for flash control. It supported a wide range of strobes including Inon Z-330/Z-240, Sea & Sea YS-D1/YS-D2/YS-250, Ikelite DS-161/DS-160/DS-125, Retra Pro (including HSS), and Subtronic Pro 270/Pro 160. Underwater Technics noted that Canon made “some changes in the R5 camera TTL protocol” compared to previous Canon cameras, requiring updated firmware in early 2021 (^[19]).

Community TTL Issues

Forum users reported TTL compatibility challenges when transitioning to the R5. One user upgrading from a Canon 7D to the R5 with Inon Z-240 strobes and a Nauticam TTL trigger reported significant underexposure (2-3 stops at f/16) in TTL mode and erratic manual mode behavior at higher power levels. Community members attributed some issues to aging strobe magnets and potential defective triggers, suggesting systematic troubleshooting (^[20]). Similar issues were reported as late as 2023, with users struggling with UW Technics boards and Inon Z-240 strobes on the R5 (^[21]).

Lens Compatibility and Recommendations

The R5 used Canon’s RF mount but was also compatible with the extensive Canon EF lens lineup via three EF-to-RF adapters: a basic adapter, one with a customizable control ring, and one with a drop-in filter mount (^[22]).

Wide-Angle Options

• Canon EF 8-15mm f/4L Fisheye USM: The most commonly recommended wide-angle lens for R5 underwater use. On full frame, it functions as either an 8mm circular fisheye (with dome shade removed) or a 15mm diagonal fisheye — but is not a true zoom between those positions due to vignetting at intermediate focal lengths. Requires a 230mm dome port and the EF-to-RF adapter (^[23], ^[24]).
• Canon RF 14-35mm f/4L IS USM: A native RF rectilinear zoom. Required a 230mm dome port and stopping down to f/11-16 for sharp corners. Some users added the Sea & Sea correction lens for 1-2 stops improvement (^[25]).
• Canon RF 15-35mm f/2.8L IS USM: Native RF wide zoom, more expensive than the f/4 version, also requiring a large dome port.
• Canon EF 16-35mm f/4L IS USM: A popular adapted option. Required a 230mm dome and stopping down to f/11-16 for corners, with the Sea & Sea correction lens recommended for improvement (^[26]).
• Nauticam WACP-1/WACP-2: Water contact optic providing excellent corner sharpness at wider apertures than dome-and-rectilinear combinations, but heavy (4-8 kg) and expensive. Multiple forum users noted that WACP optics “will always excel in image quality over rectilinear lenses and dome ports regardless of dome size” (^[27]).

A limitation noted by community members was that the Canon RF mount’s larger diameter made it unlikely that a lens small enough for the Nauticam WWL-1 wet optic would be available, giving Sony an advantage in compact wide-angle solutions using the Sony 28-60mm kit lens (^[28]).

Macro Options

• Canon RF 100mm f/2.8L Macro IS USM: The native RF macro lens, announced April 14, 2021, offered 1.4x magnification (vs 1:1 on the EF version), a Spherical Aberration Control ring, and up to 8 stops combined IS with the R5. Available July 2021 at $1,400 (^[29]). However, forum users reported a known issue: focus shift when stopping down the aperture, which could be problematic at 1.4x magnification underwater (^[30]).
• Canon EF 100mm f/2.8L Macro IS USM: The adapted EF version. Multiple forum users reported slower autofocus with this lens on the R5 (via EF-RF adapter) compared to native EF bodies like the 70D and 90D. One user returning from Anilao described the AF as poor underwater, missing many macro opportunities, and noted the same lens focused faster on older Canon DSLRs (^[31]).
• Canon RF 85mm f/2 Macro IS STM: A less expensive native RF option with 0.5x magnification, announced alongside the R5 at $599.99 (^[32]).

Underwater Performance

Autofocus

The R5’s Dual Pixel CMOS AF II system with deep-learning-based subject tracking was a major draw for underwater photographers. The system’s ability to track human, animal (dog, cat, bird), and vehicle subjects worked well for larger marine life. However, community experience was mixed for macro photography, particularly with adapted EF lenses where AF speed was notably slower than on native Canon DSLR bodies (^[33]).

Forum member Phil Rudin, a prolific reviewer, noted that he suspected the R5 and Sony A7R IV had “about the same AF speeds overall” and that to gain a noticeable advantage one would need the Sony A1 (^[34]). Users upgrading from Canon DSLRs specifically mentioned the R5’s eye autofocus and IBIS as the biggest benefits for underwater work (^[35]).

Video

The R5’s 8K and 4K video capabilities were a key differentiator, but were limited by overheating and recording time restrictions. Canon had built a timer into the camera that shortened recording time regardless of actual sensor temperature — a concern noted by early adopters for underwater video use (^[36]).

The July 2021 announcement that the Atomos Ninja V+ was compatible with existing Nauticam Ninja V housings addressed this limitation: the Ninja V+ enabled 8K/30p ProRes RAW recording from the R5, bypassing internal recording limits and overheating concerns. Nauticam noted: “Gone are the days of having to worry about recording limits or overheating issues!” (^[37])

In detailed comparisons between the Canon R5 C, Sony A1, and Nikon Z9, forum member dreifish found the R5 C (and by extension the R5’s sensor) offered the most efficient RAW compression (Cinema RAW Light files 75% the size of Nikon N-RAW) and the best oversampled 4K/60p quality in LongGOP format. The R5 C was considered the winner for “most usable 4K60 LongGOP format” (^[38]).

Comparison with Competitors

The R5 was frequently compared to the Sony A7R IV and Nikon Z-series in the Wetpixel community:

• vs. Sony A7R IV: The Sony had an advantage in compact wide-angle setups via the WWL-1B wet optic with the Sony 28-60mm kit lens. The Sony also offered a useful APS-C crop mode producing a 26MP file (vs a smaller crop on the R5), effectively extending lens reach. The R5 was considered superior for video capability. Forum member Phil Rudin stated: “you can’t go wrong with either system” (^[39]).
• vs. Sony A1: The A1 was faster overall, with a native 1/400th second sync speed and “blazing speed” autofocus. Forum consensus was that the A1 exceeded the R5 “in just about every way” for video, though at significantly higher cost (^[40]).
• vs. Canon 80D/70D (upgrade path): Users upgrading from Canon APS-C DSLRs to the R5 cited eye autofocus, IBIS, and significantly better video as the main underwater benefits, but noted that the improvements “won’t be as dramatic UW” as on land, and that switching to full-frame required investment in new lenses and larger ports (^[41]).

Canon EOS R5 C (Cinema Variant)

Canon announced the EOS R5 C on January 19, 2022, at $4,499, available March 2022. The R5 C shared the R5’s 45MP sensor and RF mount but added an active cooling fan for unlimited 8K recording, Cinema RAW Light internal recording at up to 8K/60p, Canon Log 3, timecode in/out, and Apple ProRes RAW output via HDMI. It lacked IBIS, had a physical photo/video mode switch (with a 9-second reboot between modes), and used a micro HDMI port (^[42]).

The R5 C was divisive in the underwater community. Forum member dreifish noted the “lack of the rumoured 8k60 and IBIS makes this kinda ‘meh’ compared to the already capable R5” and that “most people using the R5 underwater don’t really see [overheating] as a limitation.” Others debated whether a camera marketed as a cinema tool should lack IBIS in 2022, comparing it unfavorably to the Panasonic S1H which achieved weather sealing with its cooling fan (^[43]).

HDMI and External Recording

Both the Seacam Silver R5 and Nauticam NA-R5 housings supported HDMI 2.0 output for external recording to housed Atomos monitors. Seacam announced a companion Ninja V housing alongside the R5 housing, noting that owner Harald Hordosch designed a specific HDMI 2.0 bulkhead for the system (^[44]). Nauticam offered dedicated HDMI 2.0 cables connecting the NA-R5 to their Ninja V housing, enabling 8K ProRes RAW recording once the Ninja V+ became available with firmware support (^[45], ^[46]).

Community Discussion

The Canon EOS R5 generated extensive discussion across the Wetpixel forums, with at least 63 threads mentioning the camera. Key discussion themes included:

• Pre-announcement anticipation (March 2020): Forum users debated whether the R5 would finally push the mirrorless transition to “vast scale,” though some remained skeptical about EVFs and mirrorless AF performance versus DSLRs (^[47]).
• Canon vs. Sony debate: The R5 vs. A7R IV question became the dominant full-frame mirrorless comparison in 2021-2022, with lens ecosystem and wet optic compatibility being the deciding factors for many users (^[48]).
• Lens selection for specific applications: Detailed threads discussed optimal R5 lens choices for dolphins/marine mammals, pelagic sharks, macro, and general reef work (^[49], ^[50]).
• Upgrade economics: Multiple threads discussed the significant cost of transitioning from APS-C DSLRs to the R5 system, including new housing ($3,965+ for Nauticam), new lenses, and larger dome ports — a “small car cost” as one user described it (^[51]).
• AF comparison across brands: The R5’s macro autofocus performance versus Sony and Nikon alternatives was a recurring topic, with no clear consensus on superiority (^[52]).

Significance

The Canon EOS R5 represented a pivotal moment in the transition from DSLRs to mirrorless cameras for underwater photography. Its housing race was notable for both its breadth (seven manufacturers) and speed — Seacam announced within one week and Nauticam shipped within 10 weeks of the camera’s announcement — reflecting the mature housing manufacturing infrastructure of the mirrorless era.

The R5 also highlighted the growing cost divide in full-frame underwater photography. A complete R5 system with Nauticam housing, WACP optic, and macro lens could exceed $15,000, driving community discussions about whether the underwater benefits justified the upgrade from capable APS-C systems.

The camera’s 8K video capabilities, while headline-grabbing, proved less transformative underwater than for surface use, due to recording time limitations and the practical challenges of underwater videography. The subsequent R5 C addressed the overheating limitation but introduced trade-offs (no IBIS, higher price) that limited its underwater appeal.

Timeline

• 2020-04-20: Canon confirms R5 video specifications at live press conference: internal 8K/30p RAW, 4K/120p, 5-axis IBIS (^[53])
• 2020-07-09: Canon formally announces EOS R5 and R6 at virtual event. R5 priced at $3,899 body only, available end of July (^[54])
• 2020-07-16: Seacam announces Silver housing for R5 via Facebook (^[55])
• 2020-08-20: Ikelite announces 200DL housing at $1,695 (^[56])
• 2020-09-25: Nauticam ships NA-R5 housing at $3,965 (^[57])
• 2020-12-15: Sea & Sea announces MDX-R5 housing (^[58])
• 2021-01-16: Seacam releases full details and images of Silver R5 housing alongside Ninja V housing (^[59])
• 2021-04-14: Canon announces RF 100mm f/2.8L Macro IS USM with 1.4x magnification, available July 2021 at $1,400 (^[60])
• 2021-05-25: Underwater Technics ships TTL converter for R5 in Nauticam housings (^[61])
• 2021-06-18: Isotta ships housing at €2,790 (^[62])
• 2021-07-17: Nauticam confirms Ninja V housing compatible with Ninja V+ for 8K ProRes RAW recording from R5 (^[63])
• 2021-10-28: Inon announces housing with integrated TTL converter, shipping November 2021 (^[64])
• 2021-12-21: Marelux introduced as new housing brand with R5 support (^[65])
• 2022-01-19: Canon announces EOS R5 C cinema variant at $4,499, available March 2022 (^[66])

References

Wetpixel Live