Flicker-Free Filming
The only way to guarantee icker-free
lming at any frame rate and shutter
angle is by using pure DC power,
carbon arc sources, or daylight. There
is a chance of icker in every other
scenario with articial light, even with
tungsten mains-powered xtures.
Visible icker is also affected by
postproduction. Where the contrast is
increased, the icker becomes more
visible.
ALLEGRA-C™ has been validated
icker-free at any dim position up to
10,000 fps. ALLEGRA-C™ has been
tested across a range of dim settings,
CCTs, and colours with the high-speed
Vision Research Phantom camera
as well as Arri Alexa Mini, with the
cameras at multiple shutter angles. Not
all manufacturers are as thorough. Test
whenever in doubt, particularly when
shooting high speed.
Flicker factor, the relationship
between the maximum and minimum
illuminance exhibited in the icker, can
be measured with a icker meter. 100%
means the light goes totally dark at
minimum. HMI electronic ballasts tend
to have a icker factor around 1–3%,
tungsten lights 0–10%.
With multi-colour LED xtures, in
particular older Stage and Architectural
LED xtures where compatibility with
lm and digital cameras wasn’t a
consideration in their design, individual
colour channels can be out of sync,
causing different colour mixes on
different frames, which can cause
issues with high-speed lming, stop-
frame animation, and still photography.
If in doubt, test and review. Check the
footage after running a test, and be
aware that some digital cameras do not
replay raw footage, so it is advisable to
download les rst and then check.
Gel/Filter Emulations and
Source Matching
ALLEGRA-C™ comes pre-loaded with
a range of LEE Filter gel emulations.
Since the base spectrum of the
ALLEGRA-C™ at 3200K and 5600K is
not identical to a tungsten or daylight
source, the gel presets are merely
emulations. Due to the inherent
technology, no LED bi-colour or multi-
chip source can perfectly match the
spectrum of a subtractive lter laid
over a tungsten or daylight source.
Even if the x y coordinates appear to
be a good match, the spectrum will
be different, and the camera will read
subtle differences. If in doubt, test
before shooting.
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PANALUX ALLEGRA-C USER MANUAL ISSUE 1.0 | OCTOBER 2023
