Artur Led�chowski wrote: > > ... > My questions are: > - how big is the light loss due to bouncing the light off the umbrella? how > much more should I open the aperture - 1/2 stop. 1 stop, more?
The distance you must measure is the total light path, flash-reflector-subject. In addition you should dial in something for the scattering/loss of light due to the reflectors characteristics. I would say about a stop. BW is a forgiving film. Testing should be mandatory. > - how can the flash from the AF500FTZ affect the camera TTL-flash metering > of the burst from the Sunpack? I presume that it may fool the camera making > it underexpose its metering but I want the Pentax flash to be the key light > and the Sunpack to fill the shadows and maybe bounce a little of light off > the ceiling onto the models hair... > ... Use the key light in manual moded as well. If the AF500FTZ is not the key light you have to add that in your calculation. 1 to 2 stops under or even more can be assumed, depending on the ratio you like and want between key and fill lights. Test. HTH, Flavio
