Lighting to shoot full body.

I'm going to be shooting yoga poses in an unfinished gym area. White walls. I have two Godox 600 units, a Godox 120 deep octo box, a 42" umbrella that I can shoot through or use as a reflector. I also have a 30 in beauty dish with diffuser and a backround stand with a white cloth.
My plan is to use the white wall as backround, keeping the subject as far from it as possible. I will probably be shooting with a 35mm to close the distance.
Put the octo pretty much center, using the backround stand and white cloth as a reflector to one end of the subject and the other light shooting through the umbrella as fill to the other end. This will be the first time shooting with this equipment. My experience is limited to using off camera flash and pocket wizards.
Any suggestions or advice would be greatly appreciated.

I am ASSUMING you are shooting with FF, not with APS-C

35mm on FF at 8' from subject captures FOV of 8.3' x 5.5' at the subject distance of 8', so if your subject is 7' from white wall your lens is seeing 15.4' x 10.3' of the wall...I hope you are taking that into consideration, both size of wall area that you can capture unobtrusively without distracting elements entering the photo and how you light that wall to accentuate focus of the viewer your subject. Your issue is not merely one of illumination of the subject him/herself

In a small- to medium-sized room with white walls and ceiling, you can probably get by with a single light source. In fact, if this is your first time out with the new equipment, I'd definitely recommend getting some poses done with a single light, and once you've accomplished the basics of what you need for the shoot, add a second light.

Does the 120cm octobox have a front diffusion panel? Use it, and the light will scatter enough that you'll get fill from light that bounces off the walls, ceiling, and floors. Especially if you're using a white background (wall), you don't have to worry too much about edge lights, rim lights, etc.

How big is the gym area? Can you get in there in advance to do some testing? Or, at least carry your camera in there to get some idea of framing and perspective? Like Wilt says, if you're shooting with a 35mm you're likely going to see a LOT of the background. Opinion: If you have room to move around in the gym, stand farther away and use a longer focal length.


Here's a behind-the-scenes of my home studio with a single light (22" square octobox) on a boom directly above the camera axis, and 10-foot white ceilings:
https://flic.kr/p/EYEN​Bj

And here's the kind of result I can generally get - this has a little extra set dressing, but the lighting and backdrop are the same. Note the focal length - by standing far away (down the front hall) and shooting from waist-height with a long focal length, I can make sure to only include the portion of the backdrop that I care about. Were I to stand closer and use a shorter focal length, the backdrop would not be nearly big enough.
https://flic.kr/p/DNjL​Su


With the fill I get from bouncing off the white floor, ceiling, and backdrop, a single light is enough, and it's not even a very large light. Your octabox is twice as big, so your shadow definition will be softer and less deep.


edit, additional thought - if the yoga poses are mostly floor-based, you'll probably want to adjust the boom so the light is lower.

nathancarter wrote in post #18531620
In a small- to medium-sized room with white walls and ceiling, you can probably get by with a single light source. In fact, if this is your first time out with the new equipment, I'd definitely recommend getting some poses done with a single light, and once you've accomplished the basics of what you need for the shoot, add a second light.

I will comment on the above opinion: With a single light, one MUST keep in mind that due to the falloff of light intensity with distance, the background will almost never be getting the same intensity of illumination as the subject!

1. With a 'virtual point source' of light, if the subject is at 8' and the background at 16', the background will get -2EV of the light falling on the subject, so a 'white' background will come out VERY grayish!
   
2. With a 'large' source, it is 'large' only within about 2-3X the max dimension of the source and then it begins to evolve to behaving more like a point source...if your source is 48" size, and subject is 96" away, but the background is 192" away, it might not be -2EV at the background but -1EV due to it being closer to 'inverse linear' rather than 'inverse square' falloff of intensity.
   

Unless there's a reason you specifically need to shoot with strobes (aesthetically), I'd just open a window and shoot with ambient. Most yoga stuff I'm seeing is just shot on location (yoga studio) just as you describe in a bare white space with either natural light and a fill card, or very large light sources to approximate natural light. Take a look at all the Asics or Reebok yoga stuff.

IF you really want to use the lights you have it would depend on what you're trying to accomplish. Depends on how big the space is but I'd be inclined to make a DIY 8x8 scrim jim out of pvc and ripstop, shoot through that to light the subject, maybe position the setup and subject so that there is wall on the side bouncing some of that light back opposite and providing fill, or just have a large reflector/v-flat; and then have another lighting hitting the background to keep it from getting too dark.