[Pentaxor]

to those who own a flash unit with dual flash like the Metz 58 or Promaster 5750/7500,etc..., do you use the secondary flash for fill-in or use the built-in pop-up flash instead? which one do you prefer using and why? had you tried using both the secondary flash and built-in flash simultaneously altogether with the primary head flash? if so, what is the purpose of you doing so? is it to increase power or light distribution or use the pop-up flash for wireless slave trigger or commander?

[Pentaxor]

also, I'm not sure if the built-in camera flash has more power or higher GN number than the secondary flash flash on either Metz, Promaster,Bower and others. any info will be appreciated.