The tool is intended to assist with exposure when one camera setting has to change. Example usage scenarios include when a higher frame rate needs to be used for slow motion, when the T-stop has to change for depth of field, or when the shutter angle has to change to minimize flickering in artificial light.
To use this tool, enter the initial camera settings at the top, then add the new values with the changed setting(s) below. If necessary, one can then try various combinations to achieve an exposure difference as close to zero as possible. Any remaining difference can then be compensated by using the Exposure Assist / FLUT™ setting in post-production. ISO is not included because this can be adjusted in post-production and only applies to the camera's metadata.
Note that results are only intended as an initial estimate. The precise light transmission at a given ND filter strength or T-stop setting can differ slightly from the manufacturer label, for example. A positive exposure difference means that the new settings record more light, and vice versa.
The shutter can be input as either a shutter angle in degrees or a shutter speed in seconds, which can be typed as either a fraction or a decimal.