Utility

IR exposure calculator

Meter the scene without the filter, tell it which filter goes on, and it hands you a starting shutter speed at the same aperture and ISO. Starting point, not gospel: filters, sensors, and light all vary, so bracket from here.

Filter going on the lens

Metered shutter speed, no filter

Same aperture and ISO you plan to shoot at.

Camera is not converted stock hot mirror still inside

Suggested shutter speed

1/30

Stop costs follow the filter reference table. Focus and metering habits are in focusing and exposing in IR.