Depth of field and pulling focus on steadicam or gimbals while solo

[chris ware]

Hello

I'm curious if anyone uses an application that one can download to help with the range of depth of field for a given lens, based the T or F stop that is set, and the sensor size. I'm asking because I'm using a Steadicam and I want to know the range of distance my subject need to be in so that they are in focus. I don't have a first AC to pull focus, so I'm hoping I can get some guidance from application technology.

Also, what do folks recommend regarding camera to subject distance? I don't have anyone to help measure. I see that redrock micro has a laser, however I'm not too keen on pointing lasers at someones face.

I'm trying to use Steadicam and gimbals solo, at a shallow depth of field. I need to know that at lets say, T2, my distance to subject must stay withing a 3' range after I do the initial focus.

Any ideas on this?

thanks!

 

[Andy Jarosz]

These apps have existed since time immemorial; pCam is the best one for cinematography, but a search for "DOF" calculator will yield a lot of results.

 

[chris ware]

Thank you!!!

What do you recommend for digital measuring tape?

 

[Tom S]

I use PCAM Pro. The RED app which is free has a DOF calculator. Do not use Digital DoF (Indie Film Gear) - damn thing never worked for me. For me the list of cameras disappeared 80% of the time, really inconvenient.

 

[chris ware]

Thx

 

[Satsuki Murashige]

Honestly, this is a perfect use case for autofocus, as it exists on Canon C series cameras and the new Sony FX9.

I think you’ll find that at T2 on a S35 sensor size and at normal Steadicam working distances, your depth of field will be so shallow that trying to calculate zone focus will be somewhat pointless. Usually, in these solo situations I see people stopping down as much as possible to give themselves a fighting chance. But maybe if you are using ultra wide focal lengths, you might be ok.

I also suggest using pCAM. For measuring tapes, a 16’ Stanley Fatmax and a Leica Disto or Hilti are common tools. If your hands are already full with the gimbal or Steadicam then maybe something like this would be better: https://www.indiegogo.com/projects/cinerangefinder-cinematography-ac-accessory#/

 

[chris ware]

Massive thanks!! The autofocus on the fx9 is impressive. I appreciate your help.