Sun / Sky and unsaturated renders.

[ripe]

Hi everyone.

I visit the forum lots as I use Vray daily, found many useful tips, so many thanks !

I've only recently started using the Sun system and have a scene using standard settings as per all the tutorials. I'm using Irr map and Light cache and i'm using the physical camera.

I've modeled the scene, a small shop front with windows in the front and a door, no other lights so the sun is doing all the work with the GI. I've got everything looking nice with regards to the lighting for the internal structure, so I thought i'd cracked it. The when I started to add all my interior objects as Xrefs, I noticed a problem. The objects look really light and 'burnt out' ? I can remedy this to a degree with tweaking the lighting / camera / colour mapping (Reinhard seems to be working best for me) but this obviously darkens the whole interior of the scene. It looked really nicely, evenly lit with just the walls / floor and ceiling. Any ideas how to put the punch / saturation etc back into the scene without spoiling the overall lighting ? Sorry no image as i'm not at work now, just thought i'd post to see if this rang any bells with anyone ? Thanks guys. PS. Vray 1.5, & Max 9 only just got my Dongle and Max 2008 has being in it's box for a while, dare not update mid project !

Andy.

[percydaman]

your materials might be too light. try darkening them.

[ripe]

your materials might be too light. try darkening them.

Hi Percydaman, thanks for the reply.
The objects / materials are pretty simple, mainly images as the job i'm doing is for a gallery. The objects / materials render out just fine when I render them on their own using GI, the standard camera and just white in the environment slot to take care of the GI. (no vray sky / sun etc, just a bog standard set up to test the objects as they all are xrefed into the main scene). I don't want to darken each object / material as many i'll be using are from my library of objects that I use without problems in other, non sun/sky scenes.

[glorybound]

sun

Each scene seems to have its own brain. I look at each material as its own in the scene. Some I darken almost black and some I leave alone. I have also found that clamping output to 1 works well. Basically, my understanding, clamping output locks float point to 1 (if you chose 1), which keeps from over exposing.

[Neilg]

I don't want to darken each object / material as many i'll be using are from my library of objects that I use without problems in other, non sun/sky scenes.

Then start using a colour correct on all of your bitmaps and adjust them in each scene - you cant put the same image through 2 different lighting setups and expect it not to look different.

Its not a bad habit to get into making all of your main shaders (less important with internals) from scratch for every scene.

[^Lele^]

Each scene seems to have its own brain. I look at each material as its own in the scene. Some I darken almost black and some I leave alone. I have also found that clamping output to 1 works well. Basically, my understanding, clamping output locks float point to 1 (if you chose 1), which keeps from over exposing.

Floating point Color Clamping and exposure are unrelated, as far as i understand them.
Clamping will CUT any value which is above the set value (1.0 at default, corresponding to 255 rgb white).
But that won't stop you from overexposing an image to complete 8-bit whiteness, clamping or not.
In fact, say you set sun and sky up, and then set the physcam isos from their default to something 100 times greater.
The image will be blown out with or without clamping, only you won't be able to recover the "super-whites" in post if you clamp the image to 1.0.

As far as materials and maps go, do a search on the forum, as there's posts from Vlado explaining how real life materials are way darker than what normally is set up in an 8bit pipeline, along with a tutorial (tips and tricks section) and a script to mass darken maps and materials in a scene, to aid contrast and exposure, along with render speed, under VRay sun, sky, and physical camera.