Vray sun and diffuse shadows

[tricky]

I was on site yesterday and took photos for a model to be dropped into. Unfortunately, although bright and warm, it was a cloudy day, so I ended up with very (very very) diffuse shadows from the sun.

What is the best way to replicate this in Vray? I am using the vraysun/sky and so far have just ticked off the vraysun, so the vraysky is lighting my scene. This isn't bad, but I guess I am losing the softness from the sunlight itself. By doing this, I have also had to drastically compensate the vraycamera settings as the scene renders very dark when the sun is switched off. I have also had to dramatically edit the white balance of the camera to prevent whites from rendering quite intense blue.

In a nutshell: What is the best method to achieve softer shadows from the vraysun (as though the sun is partially obscured by hazey cloud)?

[Neilg]

Turn the intensity right down and the size up?

[tricky]

That might be worth a try. Does size affect the softness of the shadows then? Didn't realise that

[tricky]

So if the product of size and intensity is 1.0, should I be able to leave the vraycamera exposure the same?

[themaxxer]

So if the product of size and intensity is 1.0, should I be able to leave the vraycamera exposure the same?

the size only affects the softness of the shadow and has no effect to the intensity

best regards
themaxxer

[glorybound]

diffused sun

what about an HDRI and no sun? If you find an HDRI that matches your photo you might get good results.

[tricky]

Thanks themaxxer - useful info.

glorybound - to be honest, we've played around with HDRIs on occasion, but I think they are very over rated and make little difference to a render. Reflections are a different matter, but we use the vraysky for those or manually add them in post anyway (HDRIs are not high enough res or controllable/varied enough). I take your point with your suggestion, but I am getting pretty good results with increasing the size of the vraysun.

Can't believe I didn't try that before!

[glorybound]

HDRI

I am actually glad to hear you say that because I have tried HDRI's a dozen times, but never really understood the hoopla!

[Neilg]

glorybound - to be honest, we've played around with HDRIs on occasion, but I think they are very over rated and make little difference to a render.

You could probably do with getting in a little bit deeper, I cant see how an image that produces a realistic range of light can be overrated - it does exactly what it says on the tin.
I find the sky good for tests, but the second I want precise control over anything I find myself regularly switching back to HDRI.

[tricky]

You could probably do with getting in a little bit deeper

Not really sure how we could go deeper?

HDR (or EXR) imaging shows much more promise with rendered output in my opinion - tweaking exposure in post is a great idea! Why have one exposure when you can have 2000!!! Our work has a hell of a lot of post production work applied to it and the HDRI lighting is quite low down on our list of priorities.

Maybe things will change in the future, but at the moment, we don't have time to create our own and the libraries we have seen/used just don't cut it.

[DaForce]

Tricky, the reason why changing the size changes the shadow is the sun.. and vray lights.. are Area lights, so incease their area increase their area shadow. Therefore.. softness.

Same way if you make a vraylight bigger the shadows are softer around the edges.

[Giovanni]

Actually, HDRI scene lighting is really the only way to go for photorealistic renderings.

Vray Physical sky is just that, only entirely procedural.

The real trick for me is to find the right HDRI map.
Incredibly, the old, good, free probes are still the only ones I can use and get the results I need.

I tested some "hires", commercial maps, and they can't hold a candle.

Sorry to steal the thread, but has anyone purchesed a HDRI maps collection that actually works?

Thank you

regards

gio

[Neilg]

These ones are pretty good - http://www.doschdesign.com/products/...Hires_DVD.html

Not tried these, but theyre supposed to be pretty good too - http://www.doschdesign.com/products/...ant_Skies.html

[DaForce]

Dosch design AFAIK have pretty crap low range in their lower exposure levels

[dominiquelaksmana]

daforce, what is "AFAIK", been trying to understand this and pretend to understand, but, well, still cant figure it out... lol