What the thread found

• The Sony F35 camera head alone draws approximately 4 amps at 14 volts, but when the SRW deck is docked to the camera in one-piece configuration, the combined power draw reaches 12 to 14 amps, which exceeds the capacity of standard MK-V post cables wired with 22-gauge wire rated for 4 to 6 amps.
• Operating high-power cameras through undersized post cables causes cable overheating, short battery runtime, damage to J-Box connections, and circuit board trace lifting due to excessive current and heat.
• Two-piece camera setup with direct on-board adapter power or separate battery powering can reduce the power demand on the post cable compared to one-piece docked configuration.
• Rewiring the MK-V post with larger gauge wire and reconfiguring auxiliary power feeds to distribute load across two battery runs can partially mitigate power delivery problems, though this modification sacrifices the AR cable run.
• Low voltage warnings on the camera display despite fully charged batteries indicate voltage drop across undersized power cables from the rig to the camera.
• Multiple accessory loads connected to the rig simultaneously, such as wireless follow focus motors, timecode generators, and video monitoring systems, further increase total current draw and compound power delivery issues.

Depends on

• The modifications described were implemented on specific individual rigs and may not be universal solutions.
• Disabling the AR cable by reconfiguring the post eliminates remote iris control capability.
• Power specifications vary depending on whether the camera head is recording or in standby mode, and whether ancillary equipment is powered from the rig.
• The Alexa draws different wattages depending on whether it is powered at 12 volts or 24 volts, and these specifications may not directly apply to the F35.

Parts

Follow Focus

Same gear or parts

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