Lighting issues for high frame rate production are not specific to any one camera. Even with the great sensitivity of modern cameras, be prepared to use a considerable amount of light. When the frame rate is doubled the amount of light reaching the sensor for each frame is halved. This is equivalent to one “stop” of light on a lens iris (i.e., T2.8 v T4) or a doubling of shutter speed (ie. 1/60th v 1/120th or 180° v 90°). The scale is logarithmic so the light is halved with each doubling of frame rate: 24, 48, 96, 192, etc. Therefore 240fps would need 3¼ more stops of light to match the light level of 24fps. This can be achieved by opening up the lens aperture by 3.25 stops (see chart).
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