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Phantom Flex Manual
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Phantom Flex Manual
light output. LED lights are subject to the electronic circuits driving them
which can create a vast array of refresh rates, but generally we have found
that LED fixtures designed for the production community will not flicker as
long as they are not dimmed.
Finally, the shutter angle on the Phantom can affect flicker as well, since a
greater shutter angle allows for a longer response time from the light. When
shooting extremely high frame rates, it may no longer be necessary to retain
a 180-degree shutter to capture the motion generally preferred for a filmic
look. A 360-degree shutter allows both more light sensitivity and reduced
flicker possibilities.
For further technical questions, feel free to contact Sean Coles in
AbelCineTech’s Los Angeles office at scoles@abelcine.com or Jamie Alac in
their NewYork office at jamie@abelcine.com.
IRIDAS Speedgrade or FrameCycler, Quantel Pablo & Baselight (FilmLight)
also have support for Phantom RAW files.
The sensor on the Phantom Flex is a very expensive item. We do not recom-
mend cleaning it without special tools and training. If any dust should land on
the surface of the sensor, it can be blown off using a hand-squeezing bulb sy-
ringe. Never use compressed air, lens cleaning fluid or lens cleaning cloths on
a sensor.
Lighting issues are not specific for the Phantom cameras but for high frame
rate photography in general. Even with the great sensitivity of modern cam-
eras, be prepared to use a considerable amount of light, the Phantom Flex,
however, has made this easier with its sensitivity of 1000ISO. Beyond illumi-
nation, the largest issue in high-speed lighting is flicker.Tungsten lights actu-
ally have a flicker rate. When powered by alternating current (AC) electricity,
the power cycles 50 or 60 times per second (depending on the country and its
power system). During the down cycle the tungsten lamp filament can dim
slightly, causing flicker.The amount of dimming is related to the type of bulb,
wattage and physical size of filament. In general, we have found that lamps
larger than 2000 watts use tungsten filaments so large that they do not have
time to cool and dim before the power cycles back up.Therefore, we recom-
mend using 2K or greater tungsten light fixtures when shooting above 120fps
in 60hz countries and 5K or greater when shooting above 100fps in 50hz coun-
tries.
Be aware that a unit such as a nine-light is NOT a large fixture but is actually
an array of smaller lights and as such can flicker. Some additional recommen-
dations are to use DC power for tungsten lights, which eliminates flicker en-
tirely. HMI and fluorescent lights are generally fine for speeds under 120fps,
as long as they use electronic ballasts. Magnetic ballasts should not be used.
HMI lights can suffer from “arc wander,” whereby a plasmatic “hot spot” can
move about within the bulb, causing an amorphous shifting movement in the
Sensor Cleaning
Lighting for High-Speed
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