With ISO set to 200, you can locate the guide number in the table (shown on the previous page), then use the formulas on the previous page to determine aperture or the optimal flash shooting distance.

For example, with ISO 200, a Flash output level of 1/1 (full), a Zoom-head position of 35 mm, the guide number is 51/167. If the Flash shooting distance is 9 meters (approximately 30 feet), the appropriate aperture is:

f/stop = 51/9 (meters) = 5.67 = approximately 5.6 f/stop = 167/30 (feet) = 5.57 = approximately 5.6

For ISO settings other than 200, multiply the guide number by the factors shown below:

ISO Setting

Multiplier

 

 

80

0.632

 

 

200

1

 

 

400

1.414

 

 

800

2

 

 

1600

2.827

 

 

For example, if the ISO in the previous example was 800 (rather than 200), the guide number is 102 (51 x 2).

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Page 190
Image 190
Kodak DCS600 manual ISO Setting Multiplier