Norfolk Astronomical Society

Exposure Value Calculator

©2003 Glendon L. Howell


Input Exposure Parameters

Exposure Value  at ISO 100
Film Speed (ISO)  
Focal Ratio  



Computed Results (See Notes Below)

EV at New ISO  
Exposure Time 1/  seconds, or
Exposure Time  seconds, or
Exposure Time  minutes

Notes:

Exposure Value - input the value found in the subject/event tables (see links on left).

Film Speed (ISO) - input the new film speed to be used.

Focal Ratio - input the effective focal ratio of the optical system configuration.

Calculated EV at New ISO - this is the new effective exposure value.

Calculated Exposure Time - this is the calculated exposure time given in fractions of a second, decimal seconds, ans minutes.