Canon R5 Older speedlights/Canon flash units with R5

[Grumps]

Hi

Having recently purchased a R5 I was trying to find out the compatibility between it and flash units.

I have 3 main flash units.

The units are (all Canon)

580EX II
MR-14EX (ring flash)
MT-26EX (twin head)

The Canon documentation for the R5 does not reference them. Newer versions of these models (MR-14EX-RT and MT-26EX-RT) are referenced in the R5 documentation.

From my technical viewpoint I cannot see why they should not (safely) operate with the R5. The hotshoe looks identical to the hotshoe of my aged 5DmkII. I have found reference that the 580EX II does (safely) work with the the R series (although I now also know that there are exceptions as some R models come with a redesigned hostshoe which then requires an adapter - but not the R5). If the 580EX II flash works OK with the R5 then I see no immediate reason as to why the other two units would be any different. I have searched the forums here for an answer. I have searched the web, but only found old reviews and pre-loved items for sale. Original literature for the MR-14EX and MT-26EX does state that they are compatible with 'all EOS cameras (but I suppose that could have been at that time, and my no longer be applicable).

Before I perform my own tests I am just asking whether anyone knows of any reason why I should not. I don't want to go frying electronic circuitry unnecessarily. Primarily for monetary reasons.

Thanks for any advice, insights, warnings, etc.

 

[Archibald]

I guess the fear is that the flash trigger voltage might be high, which would fry the contact in the camera (if the voltage was indeed high).

Old flash units had really high trigger voltages (couple hundred volt) and that was no problem for ancient cameras that had robust flash contacts. Those days are long gone.

I use my old 580EX (not II) routinely with my R7 and sometimes with my R5, without any concern. The trigger voltage is said to be around 5 volts, which is safe. YMMV.

 

[Archibald]

I have the Canon MT-24EX twin light but it is mothballed. I used it years ago, I guess with the 7D II and maybe with the 7D. I did not have a problem with it or with the cameras.

I used the twin light with my MP-E65. That lens has fallen into disuse as I mostly do handheld macro nowadays. I find going higher than about 2X is tough in the field. The RF 100 L gets close enough to that and is much easier to use.

In the macro studio with everything immobile, the MP-E65 shines, but then I use continuous light and not flash.