The true sensitivity of a correctly set up Phantom HD Gold shooting at 25/24fps 180 Degree Shutter is 160 ISO. This is rated to be accurate for cinematography use.
Both large tungsten heads as well as any HMI can be used in most cases without flicker. When using any HMI lights, it is necessary to use 1000Hz HMI ballasts, most good lighting rental houses should have either 300Hz or 1000Hz ballasts.
300fps is 3.5 Stops down from 24/25fps. This means the HD Gold will be at 15 ISO at 300fps and 7.5 ISO at 600fps. The distance of a 20K is really dependant on the subject and lighting conditions shooting in. The HD Gold has low latitude when compared to film or an Alexa, whites will clip quickly. Diffusing light sources and filling dark areas improves results.
Despite these draw backs, the Phantom HD Gold is still a very good high speed camera. As well as having numerous Phantom Flex's and other high speed cameras, we still have two Phantom HD Gold's which work regularly to this day.
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