In video, the shutter speed shapes motion blur, so it is usually fixed first and brightness is set with ISO (and ND filters outside). The common choice is the 180° rule: the shutter is half the frame time, 1/48 at 24 fps, 1/60 at 30 fps. The app uses this value by default.
- Switch the exposure column to manual: tap the exposure mode switch at the top of the Exposure controls.
- Check the shutter speed reading. If it is not 1/(2 × frame rate), step to it with the − and + buttons.
- Hold the "A" button for a moment and release it. The app takes the exposure the camera would choose and turns it into manual settings, keeping the shutter where it is.
- Fine-tune with the ISO wheel. Turn on Zebra to see where highlights clip, or False Color to judge the whole frame. Both need the viewfinder to go through the GPU.
- If the picture is too bright even at the lowest ISO, use an ND filter rather than a shorter shutter: a short shutter makes motion look choppy.
If the ISO reading is highlighted, the camera has gone past the sensor's analogue gain and adds digital gain. Noise rises quickly from there; add light or open up instead if you can.
Under mains-powered lights, also see how to remove flicker.