Bruce Hamady
Active member
- Joined
- Mar 11, 2013
- Messages
- 35
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My production company has been looking for a wireless follow focus for use with our Scarlet and a DJI Ronin. We wanted something with the least amount of add on parts and cable and at a reasonable price since we don't use it everyday (but didn't want to deal with rentals). We own mostly Zeiss CP.2 primes which are stiff and not easy to turn but also have some rehoused lenses including a Duclos 11-16mm and our DP's favorite GL Optics 18-35mm T1.8. So we decided to try out a Cinegears Single Axis unit which has a combined motor and transmitter. When connected to the DTap of the AB battery we normally use to power the Red, the Cinegears motor has no problem turning any of our CP.2s or rehoused lenses.
With the Ronin, we can balance our Red with a Redvolt installed for power (no monitor) and the GL Optics 18-35mm lens. But if we add our Arri MMB-2 matte box with an ND, we don't seem to have enough back weight to balance unless we remove the ND, which is the whole point of the matte box. With the Cinegears plugged in to the Ronin's DTap. this configuration worked well and for ND we added a 77mm mount ND filter to the front of the lens. But when we tried a Zeiss CP.2 35mm T1.5, which does balance with the MMB-2 and ND, the follow focus would not turn the lens. When we moved the Cinegears DTap cable from the Ronin to an AB battery, the Cinegears turned the Zeiss lens like in our previous tests. I measured the voltage on the Ronin on another DTAP and found it was 11.6 volts on a Ronin battery showing 3/4 charge. That tells me either the battery voltage isn't high enough or more likely, the wires they used to be light weight cannot carry the voltage and current the Cinegears requires to turn a stiff lens. The Ronin batteries do say 14.8 volts but I can't get to the protected pins to see what they measure before they are connected to the system.
So the Cinegears Single Axis Standard motor has the power to drive a stiff Zeiss CP.2 lens when given sufficient voltage and current. It can operate with lower voltage and current but with less stiff lenses. For our purposes, we will probably use the GL Optics 18-35mm lens on the Ronin but I may occasionally may need to use a Zeiss prime. In that case, we may have to deal with having a dedicated battery in the operator's pouch or belt (not on the Ronin for weight savings) with a longer extension cable to the Cinegears motor.
Hope this helps other users.
Bruce
With the Ronin, we can balance our Red with a Redvolt installed for power (no monitor) and the GL Optics 18-35mm lens. But if we add our Arri MMB-2 matte box with an ND, we don't seem to have enough back weight to balance unless we remove the ND, which is the whole point of the matte box. With the Cinegears plugged in to the Ronin's DTap. this configuration worked well and for ND we added a 77mm mount ND filter to the front of the lens. But when we tried a Zeiss CP.2 35mm T1.5, which does balance with the MMB-2 and ND, the follow focus would not turn the lens. When we moved the Cinegears DTap cable from the Ronin to an AB battery, the Cinegears turned the Zeiss lens like in our previous tests. I measured the voltage on the Ronin on another DTAP and found it was 11.6 volts on a Ronin battery showing 3/4 charge. That tells me either the battery voltage isn't high enough or more likely, the wires they used to be light weight cannot carry the voltage and current the Cinegears requires to turn a stiff lens. The Ronin batteries do say 14.8 volts but I can't get to the protected pins to see what they measure before they are connected to the system.
So the Cinegears Single Axis Standard motor has the power to drive a stiff Zeiss CP.2 lens when given sufficient voltage and current. It can operate with lower voltage and current but with less stiff lenses. For our purposes, we will probably use the GL Optics 18-35mm lens on the Ronin but I may occasionally may need to use a Zeiss prime. In that case, we may have to deal with having a dedicated battery in the operator's pouch or belt (not on the Ronin for weight savings) with a longer extension cable to the Cinegears motor.
Hope this helps other users.
Bruce