For some reason the background image I add via the “Background Image” option becomes grainy. I’m using an image created in Photoshop at 3500 px width and then I do a render in Max at 800 px. The image however looks noisier than it looks in Photoshop at that resolution. Why is that? Is there something I’m missing?
That’s because V-Ray doesn’t apply any re-sampling on the image.
As for now it is best to use background images that matches the output resolution in order to avoid that issue.