Follow focus throw when pulling your own focus

[Ericsson San Pablo Chu]

Hi there, I'm curious what everyones preferred throw is when operating solo and having to pull your own focus on a follow focus in a documentary type setting? I'm asking because I'm prepping for a doc where things will be a bit unpredictable and trying to decide which gears and swing arm to use to get to an ideal 'general use' setup. 

For me, 1 turn on the follow focus knob (or 360 deg) can get a bit hard on the wrist on a long pull, and is sometimes hard to track on a fast follow... so I'm starting to lean towards less than a turn of the follow focus knob for close focus to infinite... maybe 270. Seems to me that cinema lenses with their 270 or 300 degree focus throws on the barrel, whilst ideal for a narrative setting with an experienced puller, actually sometimes have too much throw when operating and pulling focus solo (considering 300 degree on the barrel of a large-diameter/tooth lens usually equates to over a turn of the knob on the follow focus depending on gear and swing arm).

This also got me to wondering on a large-scale narrative movie,  is there a general throw focus pullers aim for generally? I guess it is dependent on the shot, but let's say for just a 'normal' shot with no extreme whips etc. would they generally map the entire focus movement from close to infinite to one turn of the knob on a wireless unit?  How does this work with manual follow focus units? Correct me if I'm wrong, but like I mentioned above, on a manual follow focus, even on a 1:2 arm with a large tooth gear you're still getting probably a bit over a turn of the focus knob to get from close to infinite on most lenses (unless they are really small diameter). 

Thanks ?

Edited July 6, 2021 by Ericsson San Pablo Chu
typo

[Phil Rhodes]

This concern has become a factor since more cameras started using 35mm-sized sensors and therefore required lenses with larger coverage. As a result, you end up with people taking lenses intended for single-camera drama work out on documentaries and encountering exactly this problem.

It's become sort of received knowledge that more focus throw is better. This assumption is so endemic that lenses like the Canon CN7x17 and Zeiss LWZ.3, which exist in large part to give documentarians better options, have really long focus throws in the 300-degree range which are really completely inappropriate for what they're often being used for.

In the end the idea that we need all this focus throw is barely true when you are working on a single-camera drama these days, given it's possible to remap the focus throw on a remote focus unit to almost anything you want. And as you've realised, more focus throw absolutely is not always better and that's why B4-mount broadcast lenses tend to have significantly less throw - often by half.

Personally I would prefer to take out a converted B4 broadcast lens and live with the optical losses for all the reasons of ergonomics and usability.

P