What's the trick to rendering on a white backdrop?

I use 3d max to render my designs and I have been able to create some pretty good renderings, however I have seen a certain look that I am having trouble tying to achieve.

I am talking about product renderings on a white background with a small reflection and soft shadow. I have been playing with a self-illuminated floor and backdrop to get the white, but I cant keep any reflection or shadow this way. Is there a trick to this? Does anyone know a good resource to learn this technique?

Have you tried render passes? I don’t know max, but with Cinema4D I render all layers and this way I can remove the floor and keep shadows and reflections and in turn just paste the image on a white background.

This is for brazil in 3ds but I imagine the general technique will work no matter which renderer you use:

Let us see it when you’re done. Happy new year.

If a floor (or any surface) is pure white, it is already reflecting every color in the spectrum. Therefore, there is no way to reflect a specific color (the detailed reflection of a product) on top of the white. This is true in real life and most somewhat-reality-simulating cg programs.

If a product is on a perfectly white (none really exists in reality, but one can be created in 3D) polished/reflective surface, you may, however, see faint reflections in the shadows that fall on that surface. The shadows make the surface look gray, which “leaves room” in the spectrum to see a reflection.

The easiest solution would be to render on a reflective white floor and be happy with the reflections you see in the shadows.

If you want more control, it will get more complicated. I haven’t used 3DSMAX or C4D, but I’m sure there are equivalent workarounds for those packages. In StudioTools, I would create a reflection pass with the product on a reflective black floor, then isolate the reflection by magic wanding the background in photoshop. Things are a bit easier in Maya, which has more compositing and alpha channel options, but the idea is the same. Fake the reflection, then composite it in an image editor (photoshop).

Hope this helps.

Another idea…

I’m guessing this is one way a photographer might solve the problem.

Pure mirrored floor.
Pure white self-illuminating environment or backdrop reflecting in the floor. This way the floor’s color is determined by the color of the environment/backdrop, not the floor shader. It will reflect white everywhere except where the product’s reflection falls. A disadvantage might be that the environment/backdrop will also reflect in the product.

Just a thought. Never tried it this way before. Usually just render in passes.

in 3d studio, place your product on a small white floor with a mirror finish to get the look you want. Then render it once all the way through. right click on the edge on the floor and it should tell you the RGB color. Set the environment to that color and render it again.

The environment color should now perfectly blend into your floor and will rendering out much faster than if you were trying to expand the floor to fill the entire frame. This gives you that infinite floor look with the reflectivity only where you need it.

Thanks for all the suggestions.

I also figured out another way to create this look through some tutorials and some experimentation. I have been using a matte/shadow matterial for my floor which will render out the same color as the environment and only pick up shadows, no reflection. This works great if you don’t want any reflection. However, I figured out if you basically put a standard glass surface right over the matte/shadow floor it will pick up some reflection while remaining white or whatever color you environment is. Not how its done in real life, but works pretty darn well and really lets you fine tune the reflections and shadows.

It would help to see images of what you were getting and what you wanted.

Thanks guys!

Sorry I haven’t posted any images. They are confidential.

Use a placeholder object then. That is that the teapot primitive is for…

Well, just got permission to show something I did last year that has a white background. Pro/E geometry rendered in Maya using Mental Ray. Not my part files (though I did have to generate a new assembly from what they sent).

reBang - mixed reality design (temporary upload)

The rough/angular shadow edges in the front of the object really stand out like a sore thumb. They should have feathered edges like the shadows behind the object.

Did you just use the lasso tool in Photoshop to crop the image without using the feather feature?

No photoshop work. That’s a straight render intended to be PS-manipulated by their GD dept. This is the composite of the elements (product and a floor). There were variations. They chose this one to play with.

{edit - friend just sent a link to something he’d ordered. photos are on a white ground. note the hard edge to soft: reference }