SGM G-PROFILE, User Manual

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LED refresh rate (Frequency)
About LED refresh rate
When using LED lighting with cameras, flickering can occur due to incompatible frequency settings which means the LEDs
and the cameras is not synchronised.
In order to avoid flickering and horizontal banding (rolling shutter) the refresh rate (frequency) can be adjusted in order to
achieve flicker-free performance.
Setting the LED refresh rate (Frequency) via DMX
The G-Profile offers the ability to adjust the refresh rate (frequency) of the LEDs via DMX.
By utilizing the ‘Control channel’ (channel 31 in standard mode, channel 46 in extended mode).
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See “DMX protocols” on page 38 for details.
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The refresh rate can be set between 100,00 kHz and 1,41 kHz.
It is recommended to have the G-Profile configured to operate the default refresh rate by setting the ‘Control channel’ to 0
(0%) (factory default settings) by DMX whenever possible to maintain the best possible dimming performance.
The refresh rate settings are only active as long as the value on the ‘Control channel’ is hold. The value should be stored as
a preset or as the default value for the ‘Control channel’ in the control device.
Be aware that the ‘Control channel’ is also used for fixture reset functions and DMX capture for the internal sequence editor.
When adjusting a custom value, you want to choose a frequency high enough to avoid flickering and/or horizontal banding
(rolling shutter), but low enough to maintain a good dimming performance.
Since there are differences between camera models, exposure settings etc., the optimal refresh rate settings will differ.
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In order to achieve the best result, adjust the refresh rate through a preview monitor with a feed from the cameras.
Manual_G_Profile_EN_170x113,3.book Page 21 Wednesday, December 9, 2015 10:17 AM