The flash does not fit the first Canon EOS R camera as it is only compatible with cameras that have the Multi-Function Shoe, such as the EOS R3, R6 Mark II, R7, R8, R10 and R50. The first Canon EOS R camera uses a different hot shoe, which is not compatible.

The Canon Speedlite EL-10 is compatible with your Canon EOS R50 camera. Here are the details regarding its compatibility and usage: - Compatibility: The Speedlite EL-10 is designed to be compatible with Canon cameras, including the EOS R series, of which your Canon EOS R50 is a part. - Remote mode: Yes, the Speedlite EL-10 can be used in remote mode, meaning it can be operated remotely from the camera using Canon's wireless control technology. You can use this flash with your Canon EOS R50 in both hot shoe and remote modes.

The hot shoe of the Canon Speedlite EL-10 is compatible with the Canon EOS R5 camera. The Speedlite EL-10 is a clip-on flash that has been specially developed for Canon cameras and can therefore be used with the EOS R5 without any problems.