Quote Originally Posted by df cardwell
Well, there are two controls for light:

Size, relative to the subject, and
Distance from the subject.

Distance from the subject affects the gradation across the field,
so if you want an even light across the field, you move the light back,
but if you want a variation across the field, the light belongs close to the subject.

I suppose if one is making a clinical image,
the light should be further away,
but for an expressive image, you can bring it close.
All that you've typed is true, and I don't understand the distinction you make between clinical and expressive images.

But and however, when shooting small mobile subjects in the field when and as they're found there are only two practical flash rigs. A flash bracket that somehow attaches to the camera body. A flash bracket that some how attaches to the lens or the camera's front standard. Flash brackets that stand on the ground aren't compatible with opportunistic shooting.

Both of the setups place the flash(es) near the subject, offer limited depth of illumination (I don't know if the concept is new to you, I've carried it around for decades). The best way I've come up with to get well-lit backgrounds is to have an assistant hold a flash (usually the third one) about the right distance from the background.

Obtaining, training, and keeping an assistant can be a problem. I once solved the problem by building a three-flash bracket for one of my friends. Heard his laments, went into the workshop, and emerged with a wife eliminator. And when his wife saw it, she instantly recognized what it was for. I found the thing too heavy and clumsy, but then it was really more a proof-of-concept prototype than a production version.

Come to think of it, this discussion really belongs in the lighting forum. Moderator, do your duty!