Follow Focus Backlash vs. Play

[Arnold F.]

This question is en-suite to another I posted about follow focus choices but I felt it was better in it's own thread - sometimes things get clouded here. I'm wondering if I fully understand the difference between backlash and what I'm calling "play."

Backlash has been described to me as unwanted movement at the end of a focus, and the ability to adjust it is essentially dampening or changing resistance.

Play is the word I use to describe a (usually) small difference in, or lack of, engagement between the focus knob and gear. The way I test play is to immobilize the gear in one hand and try to turn the knob with the other. The amount of play is the amount I can turn the knob without it's turning the gear.

Am I understanding these ideas and using terms correctly, and am I also correct that one wants as little play as possible?

 

[Jon Jones]

What your talking about is basically semantics. The words are interchangeable. Play would be more slang for backlash. As far as what you don't want vs. what you do want: You don't want movement in between gears inside of the FF. Movement at the end of the FF can be taken out by how close the gear is to the lens. Some people like more movement there, some like less, that is preference.
To start a thread about what the difference between two different words is kinda special, when you could have just googled it yourself.

 

[Arnold F.]

Jon - Thank you for your reply. I like to think everyone's thread is "special" in that it's a specific request for the thoughts of others, not dictated by google results. I appreciate your specific (aka "special") response.

What your talking about is basically semantics. The words are interchangeable. Play would be more slang for backlash. As far as what you don't want vs. what you do want: You don't want movement in between gears inside of the FF. Movement at the end of the FF can be taken out by how close the gear is to the lens. Some people like more movement there, some like less, that is preference.
To start a thread about what the difference between two different words is kinda special, when you could have just googled it yourself.

 

[ericyoung]

You want as little play/backlash as possible without so much pressure against the lens ring that it binds or feels steppy.

Even the best Arri/Chrosziel follow focuses have a tiny bit of backlash.