Canon EOS ELAN 7e 35mm 400 color film and external Vivitar flash

[CanonRocks777]

I just bought a used EOS ELAN 7e camera and shoot 35mm 400 speed color film in it.

My internal flash works fine but I need more flash so I also bought a used Vivitar Zoom thyristor 2500 flash.

How do I use an external flash with my camera?

Will I need to manually set my f-stop and shutter speed or will it automatically sync with it?

It looks like I can plug a cable into my flash and the body of the camera, do I need that?

If I have to manually set it, there is a chart on my flash showing f-stop and distance and I understand that but my camera has no distance indicator showing me how far an object is so I can use the chart on my flash and set f-stop manually.

How do I do this?

[Tim]

Dear CanonRocks777,

The Canon EOS Elan 7E is set up to communicate with Canon EX Series Speedlites.  If you use an external flash that is generic, so to speak, there is no guarantee that it will communicate properly with the camera.  I apologize for this inconvenience.  There is a very real possibility that, if automatic use doesn't occur, that you will need to manually set the shutter speed and aperture as well as the distance.  We wish you the best of luck using these together.