Now load your probe with the white sphere as bitmap in your material editor. Change your background image in the viewport, and get sure that you can see your white sphere, instead of the reflective sphere.

Now we want to match the skylight. For this we create a new pure white material. I use a VrayMtl, and choose in the difuse channel pure white with 255/255/255.
Now press render, and see your result.

As you can see, our 3d sphere isn´t really white. That´s because we didn´t get our hdr-image in the vray environment slot. Open your render dialog, Vray: Environment and move from your material editor the HDRI-SKYLIGHT to the GI Environment (Skylight) slot.

Your Vray Environment dialog should now look like this:





Okay, now we put the HDRI-SKYLIGHT into the right slot, now render again and you can see that we will get a grey sphere. That means, that we now have light from the skylight, but as you can see, our white color isn´t really white. Our material settings are okay, because we used a pure white. So what´s wrong with it ? The reason why our white sphere is grey, is that the light which comes from our skylight isn´t bright enough. Now it´s time to match this light information with our probe, so that our 3d sphere looks like the white sphere in the background.

To match this, we open again our material editor, select the HDRI-SKYLIGHT Bitmap and scroll down to the Output slot. Now pump up the output ammount from 1 to 1.7 and you can see the result below.

As you can see, the result is much better, but really not perfect. Our white from our vray materials doens´t match the white color from the sphere. And if you take a closer look, you can see that on the top of the sphere there is a part of white, but than it falls into grey. And you can see a little bit green touch on the left of the sphere, and that the shadows fall into more red. So, that we can match our white, we need to change the shadow and brightness values, as well as the color map.

I always start from the values I´ve taken from my reflection sphere. In this case I did the same, and I increased the ammount of brightness. Also I made the shadows more red.

The result is now much better and the white from our 3d sphere comes very close to the white from our sphere on the bg image. Of course you can make a 100% perfect white color match, but for this cg study I think it´s really okay. And it should show you, that it is very important to know, that white can be very different, and that you have to match this color information with your reference probe. If you wouldn´t do that, all your 3d objects and there materials wouldn´t fit to the background image.

Now the first step is done, and now you have to do the same with your grey sphere. So you can get sure, that your 3d created shadows, will also match the shadow from your reference probe. And so we can get sure that the shadows in our 3d environemtn will be correct calculated.

But watch out, that you don´t destroy your white color match, because you only have one HDRI-Skylight which you can match.


So you have finished the basic matching steps. With this setup you will have the possibility to fit every 3d object you want to have into your 3d scene, and the colors and shadows, and reflection will match to your bg image. How does the render work, and which tips should you know to get a good render result, I will tell you on the next sides.