Cine EI: Base ISO and Exposure Index
Base ISO and EI
In Cine EI, the selected base ISO governs capture while EI helps you judge exposure with the monitoring image. Changing EI does not directly change the recording sensitivity. Cine EI Quick can select a base ISO automatically; check your model’s instructions.
The FX30 Help Guide documents base ISO 800 and 2500. Those values and Cine EI availability should not be generalized to other Alpha or Cinema Line cameras.
Exposure changes still matter
A lower EI can prompt you to add light or open the aperture. The resulting increase in captured exposure can improve shadow signal while reducing highlight headroom. A higher EI can lead to the opposite tradeoff. EI alone does not create additional dynamic range or guarantee clean shadows.
Monitoring
Use a monitoring transform appropriate to the recorded gamma and gamut. Check whether a camera LUT affects only monitoring or is recorded into the image in the selected mode. Review a test clip before relying on the setup.