Speedlite 90EX & 270EX II Remote flash firing from EOS 5D Mark IV or R5

[Lightsmith]

I have both the 90EX and 270EXII flash units. I can't get either one to fire off camera, using either 5D MkIV or R5 bodies. They don't have master functions. When I go to flash function settings, it says imcompatible flash or power is off. Do I need a transmitter? Is there a way to fire these from the camera when not mounted on the hot shoe? Thx

[deebatman316]

You need a master (sender unit) flash unit or transmitter ie 550EX, 580EX, 580EX II, 600EX, 600EX-RT, 600EX II-RT and EL-1 series speedlite or ST-E2 transmitter. The flash units you have are slaves (receiver units). Both of your flashes require optical transmission for the flash units to fire off. Radio triggering will not work. The 600EX-RT, 600EX II-RT and EL-1 speedlites will need to be set to wireless optical triggering. The ST-E3-RT and ST-E10 are Radio only flash triggers. These sender units will NOT work.

-Demetrius

Current Gear: 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 50 F/1.8 STM, EF 85mm F/1.8 USM, EF 70-200mm F/2.8L IS III USM, 430EX III-RT, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D, Sigma 17-50mm F/2.8 EX DC OS HSM & EF 28-135mm F/3.5-5.6 IS USM

[Lightsmith]

Thanks. Disappointed that an expensive body like this won't trigger a flash off camera. The manuals for both flashes seem to indicate that some bodies will trigger the flashes. But of course they don't list cameras that do and don't work with the flashes.

[deebatman316]

Some cameras such as the 90D and 7D Mark II use the built in flash to trigger optical receivers.

-Demetrius

Current Gear: 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 50 F/1.8 STM, EF 85mm F/1.8 USM, EF 70-200mm F/2.8L IS III USM, 430EX III-RT, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D, Sigma 17-50mm F/2.8 EX DC OS HSM & EF 28-135mm F/3.5-5.6 IS USM

[jrhoffman75]

Look in your camera manuals. Both cameras have wireless (optical and radio) off camera flash triggering. You could use one flash to trigger the other in off-camera setup.

[deebatman316 · Accepted solution]

Actually the R5 and 5D Mark IV do not support any kind of wireless flash firing. Without a hot shoe mounted transmitter unit.

-Demetrius

Current Gear: 5D Mark IV, EF 16-35mm F/2.8L III USM, EF 24-70mm F/2.8L II USM, EF 50 F/1.8 STM, EF 85mm F/1.8 USM, EF 70-200mm F/2.8L IS III USM, 430EX III-RT, 470EX-AI & 600EX II-RT

Retired Gear: EOS 40D, Sigma 17-50mm F/2.8 EX DC OS HSM & EF 28-135mm F/3.5-5.6 IS USM