What the thread found

• The Alexa Mini EF mount lacks an LBUS connector for motor power, unlike the PL mount version
• Follow focus motors on EF lenses require either an AMC-1 or UMC-4 control box to function
• The UMC-4 provides lens data storage and lens mapping capabilities, while the AMC-1 offers only basic motor control without these features
• When using WCU-4 with other camera bodies like Red Epic or Sony, a UMC-4 motor controller must be mounted separately on the camera body
• Motorized follow focus on autofocus EF lenses requires manual end stop calibration since these lenses lack hard stops, and miscalibration during use will offset focus marks
• Motorized follow focus works more reliably on manual focus lenses with hard stops, such as Rokinon primes

Depends on

• Discussion is from 2016 and may not reflect current firmware or equipment options
• No firmware solution for EF lens control on Alexa Mini was confirmed, only speculation about potential future updates
• The price information provided is from 2016 and likely outdated

Parts

Follow Focus

Same gear or parts

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