The chart lists approximate guide numbers for manual flash calculations. The following equations are useful in determining the guide number (GN), aperture (ƒn), or
Guide no. (for distance in meters / feet)
Manual |
| Camera sensitivity (ISO) |
|
| GN | = dist. | |||
64 | 100 | 200 | 400 | 800 |
| ||||
flash |
| ƒn. |
|
| |||||
1/1 (Full) | 6.3 / 21 | 8 / 26 | 11 / 36 | 16 / 52 | 22 / 72 |
|
|
|
|
|
|
|
| ||||||
|
|
|
|
|
|
|
|
|
|
1/2 | 4.5 / 15 | 5.6 / 18 | 8 / 26 | 11 / 36 | 16 / 52 | GN = ƒn. X dist. | |||
1/4 | 3.2 / 10 | 4 / 13 | 5.6 / 18 | 8 / 26 | 11 / 36 |
|
|
|
|
|
|
|
| ||||||
1/8 | 2.2 / 7.2 | 2.8 / 9.2 | 4 / 13 | 5.6 / 18 | 8 / 26 |
|
|
|
|
| GN | = ƒn. |
| ||||||
1/16 | 1.6 / 5.2 | 2 / 6.6 | 2.8 / 9.2 | 4 / 13 | 5.6 / 18 |
| dist. |
| |
|
|
|
|
|
|
|
|
|
|
Flash Notes
Maxxum/Program Flash 2500(D), 3600HS(D), 5600HS(D), Macro Ring Flash 1200, and Macro Twin Flash 2400 are compatible with this camera. ADI flash metering works with the three Maxxum/Program flashes attached to the accessory shoe. See the flash manual on how to set ADI metering. The use of other flash units is not recommended.
With the Maxxum/Program Flash 5600HS(D) and 3600HS(D), the
When using the Maxxum/Program flash units, if the flash illumination is uneven at the camera’s
When using the Macro Ring Flash 1200 or Macro Twin Flash 2400 in macro mode (p. 49), light fall off toward the edges of the frame may be noticeable at the
93