Vraylight behind the camera ?

[Harutium]

I've read that some mates use a Vraylight behind the camera besides the directlight representing the Sun in Exterior stills: what is the utility of that?
Besides, I've seen that in different examples they use very different multipliers for the sun: in the Osmosis tut. the sun has m=3, and in others I,ve seen multip. of 12 or higher!
Why?
Thanks

[Phantastica]

Re: Vraylight behind the camera ?

I've read that some mates use a Vraylight behind the camera besides the directlight representing the Sun in Exterior stills: what is the utility of that?
Besides, I've seen that in different examples they use very different multipliers for the sun: in the Osmosis tut. the sun has m=3, and in others I,ve seen multip. of 12 or higher!
Why?
Thanks

The multiplier can change drastically depending on the falloff of the light. If it has an inverse square falloff and it's far away, then you'll need a really high multiplier to get enough light. A light with no falloff will probably only need a multiplier of 1 or 2.

Putting a vraylight behind the camera might emulate a camera flash, or it may just add some nice fill light to the scene. I imagine it would soften/flatten the lighting overall, which can be nice.

[Moose]

Harutium, light/sun multiplier levels depends greatly also on your colour mapping and how much light you may be trying to bounce into an interior model etc. Try a simple scene with some faces that will only be lit by bounced light, a single sun system and set you colour mapping to Exponential or HSV exponential. Then experiment by cranking your light up to various levels to see the effect of really high multipliers vs typical.