Creating dimension outside with secondary flash

Existing light (soft open shade), plus+strobe from left, (Norman 200 B from about 6 ft. though small soft box, for softer shadow edge transfer.. ), 

Now have to recommend the Pro Photo 600 B..more power, more flashes..AC and DC 

This light is set at 2/3 more, or 7 tenths more than Existing light exposure.

Example:

Ambient light reading at the subject is 1/60th of a second @ F-5.6 + 3 tenths.

Adjust light distance and power to read F-8 which is  7 tenths brighter than ambient light.

This will achieve about a 3:1 lighting ratio.

For a softer Ratio, reduce the light brightness to 5.6 + 8 tenths.

This is a half stop brighter than ambient.

If you want a 2:1 ration, set light intensity to match ambient.

In this case the flash meter would read 5.6 +3.tenths,,the same as the meter reading for ambient light.

For Bright sunlight situations.

Measure camera for ambient light reading, and set flash to 2/3rds that reading

Solution for 2:1 ratio

1 unit of light over all from ambient light.

1 unit of light on the highlight side of subject

Equals two units of light on highlight side( one ambient, one flash), and only the one unit on shadow side of subject..

This is expressed as a ratio of 2:1

Solution for 3:1 ration

1 unit of light over all from ambient light

if flash is twice the brightness of ambient, then

2 units of light on the highlight side + 1 unit of ambient is 3 units

Shadow side only receives 1 unit.

This is expressed as a ratio of 3:1

Flash on Camera Fill........(yuck)

If you use flash on camera that equals the existing light exposure this becomes 1:1 lighting

and is flat and unflattering. Like wearing a minors hat lamp. There is no dimension.

It is 1:1 because- on camera flash illuminates the same area as the ambient light.

I guess it could be expressed as 2:2 lighting.

One unit ambient + One unit of flash over both the highlight side and the shadow side of the subject..

bdr 2007