Canon EOS R5 II 8K Heat Test: 54 Minutes, One Mistake, and What Real Shooting Felt Like

I originally bought the Canon EOS R5 Mark II for hybrid work, not for stress testing. My normal workflow is a mix of short cinematic clips, product shots, handheld street footage, and occasional long interview sessions for YouTube. But after seeing endless arguments online about overheating, I became curious whether the camera would actually survive a realistic shooting day in warm conditions instead of a cold studio.

Most videos online focused on extreme cases. Either creators pushed 8K RAW until shutdown inside air-conditioned rooms, or they dismissed the problem entirely after recording a few short clips. I wanted something in between — a normal creator-style test with realistic pauses, handheld shooting, menu browsing, autofocus tracking, and repeated takes.

The interesting part is that the camera never behaved exactly the same twice. Small things changed the results more than I expected: humidity, stabilization, wireless settings, playback usage, and even how long the LCD stayed folded against the body.

By the third evening of testing, I stopped looking only at “overheat time” and started paying attention to something more important — whether the camera felt stressful to use during actual shooting. That changed my opinion completely.

My Exact Test Setup

I used the following setup for the main indoor test session:

Setting Details

Camera Canon EOS R5 Mark II

Lens Canon RF 24-70mm F2.8L IS USM

Firmware Version 1.0.1

Memory Card ProGrade Digital CFexpress Type B Gold 512GB

Recording Modes 8K 30fps IPB + 8K RAW Light

Color Profile Canon Log 2

Autofocus Servo AF + Eye Tracking

LCD Brightness Manual 70%

IBIS ON for handheld / OFF for tripod

Battery LP-E6P at 96%

Indoor Temperature 29.4°C

Indoor Humidity 68%

Test Start Time 6:42 PM

For the outdoor retest, temperature was close to 33°C after light evening rain. Humidity felt much worse outdoors than indoors, which noticeably affected cooldown speed.

I intentionally avoided external cooling fans because most buyers will not attach extra accessories during casual use.

I’ve already tested this in real-world conditions — see the full results here

The First Recording Session

I started with 8K 30fps IPB because that is the mode I would realistically use most often for YouTube and commercial editing.

The first 20 minutes felt completely normal. Autofocus stayed responsive, menus opened quickly, and the body temperature only felt slightly warm near the memory card area.

At around the 35-minute mark, I noticed something unusual during playback. The camera took slightly longer than normal to generate previews after stopping clips. Nothing dramatic, but enough that I checked the warning indicators for the first time.

Then I realized something embarrassing.

Wi-Fi was still enabled from transferring clips earlier that afternoon.

That mistake mattered because background wireless activity continued during the recording session. I disabled Wi-Fi immediately, but by then the body was already noticeably warmer than before.

The first temperature warning finally appeared at exactly 47 minutes and 12 seconds.

What surprised me most was that the camera still felt usable. The grip remained comfortable, buttons responded normally, and autofocus tracking did not suddenly collapse. Online discussions made it sound like the camera would become unstable long before shutdown, but that never happened in my test.

Recording finally stopped automatically at 54 minutes and 41 seconds.

The differences became clearer after extended usage — see the detailed results here

What the Camera Felt Like After Shutdown

This part rarely gets discussed properly online.

Most reviewers stop the test once recording ends. I paid more attention to recovery behavior because that matters more during actual client work.

Immediately after shutdown:

the CFexpress slot area felt hottest

the rear LCD panel was warm but manageable

the battery compartment felt cooler than expected

menus still worked normally

I powered the camera off completely, flipped the LCD outward, and left it untouched near an open window with indirect airflow.

After 16 minutes, the camera allowed 8K recording again.

That recovery time changed my opinion more than the shutdown itself. The original Canon EOS R5 often felt frustrating because cooldown periods were long and unpredictable. The R5 II recovered much more consistently.

8K RAW Light Changed Everything

The next evening, I switched to 8K RAW Light expecting slightly worse thermals.

Instead, the difference felt massive.

The camera body heated faster almost immediately, especially during handheld walking shots with IBIS enabled. The right rear section near the card slot became noticeably warm before the 25-minute mark.

First warning: 31 minutes and 08 seconds.

Automatic stop: 36 minutes and 17 seconds.

That was the moment I finally understood why online opinions about this camera are so divided. Someone shooting short oversampled 4K clips may never experience serious heat issues. Someone filming long-form RAW interviews absolutely will.

Codec choice changes the entire experience.

The Outdoor Test Nobody Mentions

The outdoor session taught me something I rarely see in YouTube reviews.

Humidity matters.

I repeated the RAW Light test outdoors the following afternoon. Temperature was around 33°C, but the more important detail was humidity after earlier rain. The air felt heavy and sticky.

The warning icon appeared earlier than indoors: approximately 27 minutes.

Recording stopped just after 32 minutes.

Even though outdoor airflow existed, the humid environment slowed cooldown noticeably. The camera never became dangerously hot, but it retained warmth longer between takes.

That explains why creators in tropical climates often report worse thermal performance than reviewers testing in cooler countries.

What Actually Increased Heat the Most

After repeating the tests several times, these factors affected temperatures the most:

1. RAW Recording

This was by far the largest factor. File sizes increased dramatically, processing workload became heavier, and the CFexpress card generated much more heat.

2. IBIS During Handheld Shooting

I originally underestimated stabilization heat.

Once I disabled IBIS during tripod interviews, temperature buildup slowed noticeably.

3. Playback After Recording

Reviewing clips immediately after long takes surprisingly kept the camera warmer longer. Continuous playback added extra processing instead of letting the system recover.

4. Humidity

This mattered more than pure temperature alone. Indoor tests at 29°C sometimes performed better than humid outdoor tests at similar temperatures.

What Helped the Most

These changes gave the best real-world improvements:

disabling Wi-Fi and Bluetooth completely

recording in 8K IPB instead of RAW Light

turning IBIS off for tripod work

keeping the LCD flipped outward

avoiding unnecessary playback between takes

shooting shorter segments instead of nonstop rolling

One thing that barely helped: lowering LCD brightness.

I expected brightness reduction to improve thermals significantly, but the difference was minimal compared with codec choice or stabilization settings.

Comparison With Other Cameras

Compared With the Original Canon EOS R5

The R5 II feels less stressful overall.

faster recovery times

fewer aggressive warning behaviors

better sustained usability

improved thermal management logic

The original R5 often felt like it was counting down toward shutdown. The newer model feels more predictable.

Compared With the Sony A7S III

Sony still handles long continuous recording better overall, especially in hot conditions.

However:

Canon produces sharper oversampled detail

Canon autofocus felt slightly stickier during subject tracking

Sony remained cooler during extended recording

Compared With the Canon EOS C70

The C70 still wins easily for professional uninterrupted recording because active cooling changes everything.

The R5 II feels like:

a hybrid creator camera first

a cinema substitute second

That distinction matters before buying.

I tested this beyond basic first impressions — see the detailed real-world results here

Final Verdict

After several days testing the Canon EOS R5 Mark II, I think the most important takeaway is this:

The experience depends heavily on how you shoot.

If you constantly record long 8K RAW clips in hot environments, the camera will absolutely build heat and eventually stop. No firmware update can fully overcome the physical limits of a compact weather-sealed mirrorless body.

But if your workflow involves normal creator-style shooting — shorter takes, pauses between clips, mixed photography and video, interviews, handheld B-roll, and occasional 8K usage — the camera feels dramatically more practical than the original R5 ever did.

The internet often treats overheating like a simple yes-or-no issue. After using the camera in real conditions, it felt much more nuanced than that.