Using the R8 and "old" style 5 pin flashes (e.g.,., 580 EXII, 430 EXIII RT)

[garymak1]

R8: I'd like to ask about using Canon's new flash hot shoe contact with the R8.  My understanding was that the R8 can ONLY take the new hot shoe style flashes and that you needed an adapter to use an old "traditional 5 pin" flash.  Well, I used a 430 EXIII RT on the R8 during a recent test drive with an R8 (I'm considering getting one)  and to my surprise, it worked fine without any "adapter."  I just put the flash in the hot shoe like any of my other cameras, (R5, 5Diii, G1Xiii...)  No apparent problem.  Anybody have any insights? Does the flash lose some advanced functionality but works reasonably well otherwise?  Can't get any info from Canon on this.

Thanks!

[kvbarkley]

The 5 pins should be pretty obvious as you can see in these pictures

https://kenrockwell.com/canon/eos-r/r8.htm

[garymak1]

Sorry, not sure what question that was in response to... 

[kvbarkley]

As you can see from this image:

The R8 has both the new-fangled fingers *and* the 5 pin traditional contacts, so older flashes work fine.

[zakslm]

Demetrius is the go-to subject matter expert on all speedlites and hopefully he'll respond to your question.

Until then, I asked Google Gemini (AI) about the disadvantages of using a 580EXII on an R8 and below is a copy of Google Gemini's response:

Using the Canon Speedlite 580EX II on a modern mirrorless camera like the Canon EOS R8 is possible, but it comes with several disadvantages compared to newer flashes like the Canon Speedlite EL-5.

1. Physical Compatibility & Weather Sealing

The most immediate drawback is the mounting interface. The Canon R8 features the new 21-pin Multi-Function Shoe, while the 580EX II uses the traditional 5-pin design.

• Adapter Requirement: To maintain weather sealing and ensure a secure fit, you need the Canon AD-E1 Multi-Function Shoe Adapter. Without it, the 580EX II may not sit perfectly or may lose its weather-resistant properties.

• Balancing Issues: The R8 is a very lightweight body. Adding a large flash like the 580EX II—especially with an adapter—can make the setup feel top-heavy and unbalanced.

2. Autofocus Assist Limitations

Mirrorless cameras handle autofocus differently than older DSLRs.

• No IR Beam: The 580EX II uses a red Infrared (IR) AF Assist Beam, which is completely incompatible with mirrorless sensors.

• "Disco Flash": Instead of a steady IR grid, the camera will resort to Intermittent Flash Firing (rapidly pulsing the main flash tube) to help it focus in low light, which can be distracting for subjects. Newer flashes like the EL-5 often include an LED modeling lamp that is much more effective and less intrusive.

3. Outdated Wireless Technology

The 580EX II relies on optical pulse triggering for off-camera work.

• Line-of-Sight Only: Optical triggering requires the flash to "see" the master signal. This fails if there are obstacles or if you are shooting in bright sunlight.

• Radio Advantage: Modern flashes like the EL-5 or 600EX II-RT use 2.4 GHz radio transmission, which works through walls, around corners, and over much longer distances (up to 98 feet) without interference.

4. Performance & Integration

• Battery Tech: The 580EX II uses 4 AA batteries. Newer units like the Speedlite EL-5 use a high-capacity Lithium-ion battery pack (LP-EL), offering much faster recycle times (0.1–1.2 seconds) and significantly more flashes per charge (up to 350 full-power pops).

• Menu Control: While the 580EX II is mostly compatible with the R8's internal menu, the EL-5 is designed to integrate perfectly, allowing for more seamless settings adjustments directly from the camera touchscreen or the Canon Camera Connect app.

Comparison Overview

Feature	580EX II	Speedlite EL-5
Mounting	Legacy 5-pin (Needs AD-E1 Adapter)	Native Multi-Function Shoe
Power Source	4x AA Batteries	Rechargeable Li-ion (LP-EL)
Recycle Time	~2–3 seconds (Alkaline)	0.1–1.2 seconds
Wireless	Optical Pulse	2.4 GHz Radio RT
AF Assist	Red IR (Incompatible)	LED Modeling Lamp

Summary: The 580EX II is still a powerful flash, but you will miss out on reliable autofocus in the dark, faster recycling, and modern radio triggering.,

[kvbarkley]

The extra fingers are not so much for flash functionality as to all the *other* stuff you can put in the hot shoe like microphones and I suppose GPS.  

[deebatman316]

@zakslm you got everything handled. The only other feature not available on EOS M & R series is modeling flash. Modeling flash will not fire from a speedlite if the depth of field preview button is pressed. Also Intermittent Flashing Firing isn’t going away anytime soon. When the EL-5 is paired with the R3, R7 & R10 in very low light. The LED AF Assist Beam will NOT be emitted. Instead Intermittent Flash Firing is used. Other times the LED AF Assist Beam is projected at full brightness only. Other R series cameras such as the R8 can vary the brightness output of the LED AF Assist Beam. Or the camera body can emit the beam. The EL-10 retains Intermittent Flash Firing while dropping the LED AF Assist Beam.

[garymak1]

Thanks! That's what I figured.  If it were not so, the flash wouldn't have worked on the R8.  I use mostly "M" but tested it with TTL as well, and it was fine.  According to Canon, you MUST use the "adapter" but they don't explain why.  I didn't use the adapter and it worked.  As I suspected, there are some advanced functions that you lose, but some of them have nothing to do with the pin-configuration so much as the technology that's in the newer flashes.

[deebatman316 · Accepted solution]

@garymak1 the only cameras that require the adapter are the EOS R50 & EOS R50V. That's because the hot shoes on those cameras lack the legacy 5 pins for older flashes. But the adapter doesn't bring any new features for older style flashes. The adapter also allows you to maintain a weather sealed connection with weather sealed speedlites such as the 600EX II-RT. Other speedlites such as the 430EX III-RT don't have any weather sealing so its not necessary to use.

[garymak1]

So, thanks for the AI search.  A few things.

1)"Using the Canon Speedlite 580EX II on a modern mirrorless camera like the Canon EOS R8 is possible, but it comes with several disadvantages compared to newer flashes like the Canon Speedlite EL-5." Sure, of course.  A 10 year old camera, for example, won't have all the new technology of a brand new camera.  Similarly, a 15 year old flash won't have all the new technology of a new flash.

2) "The 580EX II relies on optical pulse triggering for off-camera work."  This assumes one is configuring a vast network of flash systems based on using the one flash's internal technology from the hot shoe to trigger it.  I have always used electronic remote radio triggers (like RadioPopper) so this is not a consideration or problem.

3) Battery Tech: The 580EX II uses 4 AA batteries. Newer units like the Speedlite EL-5 use a high-capacity Lithium-ion battery pack (LP-EL), offering much faster recycle times (0.1–1.2 seconds) and significantly more flashes per charge (up to 350 full-power pops).  Using AA rechargeable that are compatible with a wide-range of other electronics and can be swapped in and out quickly is not necessarily a disadvantage. And using the CP-F4N external power pack (which also takes AA batteries) pretty much negates any recycling time and length of time for shooting issues vs. E5.  (I use this on shoots all the time and after a very long time of several hundred shots, if I notice a few skipped flashes, I just swap all of them out.)

4. Menu Control: While the 580EX II is mostly compatible with the R8's internal menu, the EL-5 is designed to integrate perfectly, allowing for more seamless settings adjustments directly from the camera touchscreen or the Canon Camera Connect app. A bit of AI vague platitudinal statements here.

5. AF Assist/Red IR (Incompatible): Yes, this is an important point if using ETT-L, although this is not a problem of 5 pin vs. 21 pin, (and I usually use Manual anyway.)

6. Finally, many of the issues raised above in the AI search describe the issues relating to using a flash with older features/lack of newer features, that have nothing to do with 5 pin vs. 21 pin hot shoes so much as the old flash simply lacks the feature or is, as in the case of IR vs. LED AF assist, for example, a different technology.  All those issues are inherent to the features contained in the older device itself, not whether the 5 pin flash won't work at all on a 21 pin hot shoe camera such as the R8.  

What I conclude then is: if I don't use the "adapter" with a 580 EXII, it will work on an R8 minus any inherent difference in technology (e.g., IR vs. LED AF assist,); if I do use the adapter, the 580 EXII will still work, and won't have any more capability than if I used it with the "adapter."

The main question was the deliberate impression that Canon gave that with an R8 (or any such "new 21 point hot shoe flash) you MUST use an adapter otherwise the devices, e.g., old flashes, GPS, etc, will not work.  That, as I found out from my tests, and as you've outlined, is simply not true.  (Thanks for your honesty, Canon!).

The question is what features won't work due to using a 5 pin hot shoe flash on a 21 pin hot shoe camera, not what features on an old flash won't work because they don't exist on a new camera anyway: best example, AF Assist/Red IR.

Thanks again for taking the time.  Good constructive food for thought.  Thanks!