How can I make my 580 EX II work more like a Vivitar 283?

[ih8quark]

I apologize if this is a newbie question, but I’m having a real problem with my 580 EXii. I can’t seem to figure out what settings to set the camera/flash at to make it mimic the old Vivitar 283/285. 
I used to shoot weddings, And I knew back, then that if I set the settings on the flash and camera, that everything within 15 to 30 feet would be properly illuminated, and I just can’t figure out how to do that on my canon flash.and I knew back, then that if I set the settings on the flash and camera, that everything within 15 to 30 feet would be properly illuminated, and I just can’t figure out how to do that on my canon flash.

I would appreciate any assistance, and sorry if this is a stupid question

[deebatman316]

What mode is the speedlite set to. In E-TTL the camera will figure out how much power is needed. What camera are you using.

[ih8quark]

I’m in E – TTL using a 5D mark three and a 5DS. The question I’m running into is where should I be setting the aperture and shutter speed?I’m in E – TTL using a 5D mark three and a 5DS. The question I’m running into is where should I be setting the aperture and shutter speed?
back in “the old days“ I would set the shutter speed, the same as my ISO, and then the flash would tell me what aperture I should set out for an acceptable illumination. Can’t seem to figure that out… Maybe I’m just too old! Appreciate the assist

[deebatman316]

E-TTL figures all that out the flash power. All you need to do is set your Aperture, ISO and shutter speed on the camera. You don't need to set anything on the speedlite. When using auto exposure modes ie Av, TV, P & Full Auto. The camera treats flash as fill flash. In Manual mode it treats it as main light. E-TTL is adverse to blown highlights.

[MikeSowsun · Accepted solution]

The Canon 580EX II is designed to use ETTL metering to automatically adjust flash power to what ever is set on the camera. I usually use ETTL with the camera in Manual mode. The flash will automatically know what the aperture is and provide the correct amount of flash power.

With straight ahead flash, the effective flash range will be displayed and you can see it change with any adjustments to aperture, ISO, or zoom head focal length. 

BUT…. The 580EX II also has Custom Function 5 that lets you change the Auto Metering from ETTL to “External Metering”. This is an Auto Thyristor mode with the exposure sensor on the front of the flash, just like your Vivitar 283.

Auto External with EOS cameras will match the aperture and ISO you have set on the camera.

Manual External requires you to manually set the aperture and ISO to match the camera settings.